GD(w/o STI)-11
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
2. Diagnostic Trouble Code (DTC) Detecting Criteria
A: DTC B1570 ANTENNA
1. OUTLINE OF DIAGNOSIS
2. ENABLE CONDITIONS
When starting the engine.
3. GENERAL DRIVING CYCLE
Perform the diagnosis only after starting the engine.
4. DIAGNOSTIC METHOD
Judge as NG when the conditions for the outline of the diagnosis of the top are established.
DTC Item OUTLINE OF DIAGNOSIS
B1570 Antenna Faulty antenna
B1571 Reference Code Incompatibility Reference code incompatibility between body integrated unit and ECM
B1572
IMM Circuit Failure (Except Antenna Cir-
cuit)
Communication failure between body integrated unit and ECM
B1574 Key Communication Failure
The body integrated unit to confirm the key (transponder) ID code has
malfunction, of the transponder is faulty.
B1575 Incorrect Immobilizer Key
Incorrect immobilizer key (Use of unregistered key in body integrated
unit)
B1576 EGI Control Module EEPROM ECM malfunctioning
B1577 IMM Control Module EEPROM Body integrated unit malfunctioning
B1578 Meter Failure
Reference code incompatibility between combination meter and body
integrated unit
15WRX_STI_US_EN.book 11 ペー   
GD(w/o STI)-12
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
B: DTC B1571 REFERENCE CODE INCOMPATIBILITY
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC B1570. <Ref. to GD(w/o STI)-11, DTC B1570 ANTENNA, Diagnos-
tic Trouble Code (DTC) Detecting Criteria.>
C: DTC B1572 IMM CIRCUIT FAILURE (EXCEPT ANTENNA CIRCUIT)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC B1570. <Ref. to GD(w/o STI)-11, DTC B1570 ANTENNA, Diagnos-
tic Trouble Code (DTC) Detecting Criteria.>
D: DTC B1574 KEY COMMUNICATION FAILURE
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC B1570. <Ref. to GD(w/o STI)-11, DTC B1570 ANTENNA, Diagnos-
tic Trouble Code (DTC) Detecting Criteria.>
E: DTC B1575 INCORRECT IMMOBILIZER KEY
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC B1570. <Ref. to GD(w/o STI)-11, DTC B1570 ANTENNA, Diagnos-
tic Trouble Code (DTC) Detecting Criteria.>
F: DTC B1576 EGI CONTROL MODULE EEPROM
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC B1570. <Ref. to GD(w/o STI)-11, DTC B1570 ANTENNA, Diagnos-
tic Trouble Code (DTC) Detecting Criteria.>
G: DTC B1577 IMM CONTROL MODULE EEPROM
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC B1570. <Ref. to GD(w/o STI)-11, DTC B1570 ANTENNA, Diagnos-
tic Trouble Code (DTC) Detecting Criteria.>
H: DTC B1578 METER FAILURE
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC B1570. <Ref. to GD(w/o STI)-11, DTC B1570 ANTENNA, Diagnos-
tic Trouble Code (DTC) Detecting Criteria.>
15WRX_STI_US_EN.book 12 ペー   
GD(w/o STI)-13
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
I: DTC P000A A CAMSHAFT POSITION SLOW RESPONSE (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect the AVCS system malfunction.
Judge NG when the amount of AVCS actual timing advance does not approach to the amount of AVCS target
timing advance.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis continuously while AVCS is operating.
4. DIAGNOSTIC METHOD
When the differences of target timing advance amount and actual timing advance amount is calculated dur-
ing AVCS control, and the difference per predetermined time is the specified value or larger.
Judge as NG when the following conditions are established within the predetermined time.
Time Needed for Diagnosis: 25 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
J: DTC P000B B CAMSHAFT POSITION SLOW RESPONSE (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect the exhaust AVCS system malfunction.
Judge NG when the amount of exhaust AVCS actual timing advance does not approach the amount of ex-
haust AVCS target timing advance.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis continuously while exhaust AVCS is operating.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
AVCS control In operation
Target timing advance change amount (per 80 ms) < 4°CA
Judgment Value
Malfunction Criteria Threshold Value
Σ(Target position – Actual position) > 4000°CA
or
< –4000°CA
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Exhaust AVCS control In operation
Target timing advance change amount (per 80 ms) < 4°CA
15WRX_STI_US_EN.book 13 ペー   
GD(w/o STI)-14
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
4. DIAGNOSTIC METHOD
When the differences of target timing advance amount and actual timing advance amount is calculated dur-
ing exhaust AVCS control, and the difference per predetermined time is the specified value or larger.
Judge as NG when the following conditions are established within the predetermined time.
Time Needed for Diagnosis: 25 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
K: DTC P000C A CAMSHAFT POSITION SLOW RESPONSE (BANK 2)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P000A. <Ref. to GD(w/o STI)-13, DTC P000A A CAMSHAFT PO-
SITION SLOW RESPONSE (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>
L: DTC P000D B CAMSHAFT POSITION SLOW RESPONSE (BANK 2)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P000B. <Ref. to GD(w/o STI)-13, DTC P000B B CAMSHAFT PO-
SITION SLOW RESPONSE (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>
Judgment Value
Malfunction Criteria Threshold Value
Σ(Target position – Actual position) > 4500°CA
or
< –4500°CA
15WRX_STI_US_EN.book 14 ペー   
GD(w/o STI)-15
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
M: DTC P0010 "A" CAMSHAFT POSITION ACTUATOR CIRCUIT/OPEN (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect the open/short circuit of oil control solenoid valve.
Judge as NG when the current is small even though the duty signal is large, or when the current is large even
though the duty signal is small.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Diagnosis 1
Diagnosis 2
Time Needed for Diagnosis: 2000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Diagnosis 1
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Oil control solenoid control duty 99.6%
Diagnosis 2
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Oil control solenoid control duty < 8%
Judgment Value
Malfunction Criteria Threshold Value
Oil control solenoid control present current < 0.306 A
Judgment Value
Malfunction Criteria Threshold Value
Present current of the oil control solenoid 0.306 A
15WRX_STI_US_EN.book 15 ペー   
GD(w/o STI)-16
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
N: DTC P0011 INTAKE CAMSHAFT POSITION - TIMING OVER-ADVANCED OR
SYSTEM PERFORMANCE (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect the AVCS system malfunction.
Judge as NG when the conditions during which the differences of AVCS target timing advance amount and
AVCS actual timing advance amount is large continues.
2. ENABLE CONDITIONS
•Normal
Intermediate lock
3. GENERAL DRIVING CYCLE
•Normal
Perform the diagnosis continuously while AVCS is operating.
Intermediate lock
Perform the diagnosis when the AVCS is carrying out the intermediate lock control at the engine start.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
AVCS control In operation
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Engine speed 500 rpm
Elapsed time after starting the engine > 500 ms
and
Value from Map
Map
Engine coolant temperature
°C (°F)
–40
(–40)
–30
(–22)
–20
(–4)
–10
(14)
0
(32)
10
(50)
20
(68)
30
(86)
Elapsed time after starting the engine
s
10 10 10 8 5 4 3 3
Engine coolant temperature
°C (°F)
40
(104)
50
(122)
60
(140)
70
(158)
80
(176)
90
(194)
100
(212)
110
(230)
Elapsed time after starting the engine
s
33344444
15WRX_STI_US_EN.book 16 ペー   
GD(w/o STI)-17
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
4. DIAGNOSTIC METHOD
When the conditions during which the differences of AVCS target timing advance amount and AVCS actual
timing advance amount is large continues for certain amount of time.
Judge as NG when the following conditions are established within the predetermined time.
Time Needed for Diagnosis:
Normal: 10 seconds
Intermediate lock: 2 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
• Normal
|Vtd|
Vtd = VVT target position – VVT actual position
> 10°CA
• Intermediate lock
|Vtd|
> 10°CA
15WRX_STI_US_EN.book 17 ペー   
GD(w/o STI)-18
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
O: DTC P0013 B CAMSHAFT POSITION ACTUATOR CIRCUIT/OPEN (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect the open/short circuit of oil control solenoid valve.
Judge as NG when the current is small even though the duty signal is large, or when the current is large even
though the duty signal is small.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Diagnosis 1
Diagnosis 2
Time Needed for Diagnosis: 2000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Diagnosis 1
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Oil control solenoid control duty 99.6%
Diagnosis 2
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Oil control solenoid control duty < 8%
Judgment Value
Malfunction Criteria Threshold Value
Oil control solenoid control present current < 0.306 A
Judgment Value
Malfunction Criteria Threshold Value
Present current of the oil control solenoid 0.306 A
15WRX_STI_US_EN.book 18 ペー   
GD(w/o STI)-19
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
P: DTC P0014 EXHAUST AVCS SYSTEM 1 (RANGE/PERFORMANCE)
1. OUTLINE OF DIAGNOSIS
Detect the exhaust AVCS system malfunction.
Judge as NG when the conditions during which the differences of exhaust AVCS target timing advance
amount and exhaust AVCS actual timing advance amount is large continues.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis continuously while exhaust AVCS is operating.
4. DIAGNOSTIC METHOD
When the conditions during which the differences of exhaust AVCS target timing advance amount and ex-
haust AVCS actual timing advance amount is large continues for certain amount of time.
Judge as NG when the following conditions are established within the predetermined time.
Time Needed for Diagnosis: 10 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Exhaust AVCS control In operation
Judgment Value
Malfunction Criteria Threshold Value
|Vtd|
Vtd = VVT target position – VVT actual position
> 10°CA
15WRX_STI_US_EN.book 19 ペー   
GD(w/o STI)-20
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
Q: DTC P0016 CRANKSHAFT POSITION - CAMSHAFT POSITION CORRELA-
TION (BANK1)
1. OUTLINE OF DIAGNOSIS
Detect the AVCS system malfunction.
Judge as NG when standard timing advance amount is far from learning angle.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis continuously after starting engine and while AVCS is not operating.
4. DIAGNOSTIC METHOD
Judge as NG when the absolute value of the difference between cam signal input position and learning value
is out of specification.
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Diagnosis 1
Diagnosis 2
Time Needed for Diagnosis: 1 second
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
NOTE:
Initial standard learning value is the value of crank angle initially input at the production plant. And then it will
be updated every time normal judgment has been completed. Learning value will not be updated if NG judg-
ment occurs because timing belt or chain derails suddenly in process or because wrong assembly occurs
during servicing.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Elapsed time after external load (power steering, neutral position switch) change 3 s
AVCS position learning In operation
AVCS position learning experience flag
(Only used for diagnosis 1)
Set
Judgment Value
Malfunction Criteria Threshold Value
|Crankshaft position when camshaft position sensor signal is input – Learning
value|
> 10°CA
Judgment Value
Malfunction Criteria Threshold Value
Camshaft position sensor signal input position < 53°CA
or
> 112°CA
15WRX_STI_US_EN.book 20 ペー   
GD(w/o STI)-21
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
R: DTC P0017 CRANK AND CAM TIMING B SYSTEM FAILURE (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect the exhaust AVCS system malfunction.
Judge as NG when standard timing advance amount is far from learning angle.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis continuously while the exhaust AVCS is not operating after warming up.
4. DIAGNOSTIC METHOD
Judge as NG when the absolute value of the difference between cam signal input position and learning value
is out of specification.
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Diagnosis 1
Diagnosis 2
Time Needed for Diagnosis: 5 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
NOTE:
Initial standard learning value is the value of crank angle initially input at the production plant. And then it will
be updated every time normal judgment has been completed. Learning value will not be updated if NG judg-
ment occurs because timing belt or chain derails suddenly in process or because wrong assembly occurs
during servicing.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Elapsed time after external load (power steering, neutral position switch) change 3 s
Exhaust AVCS position learning In operation
Exhaust AVCS position learning experience flag
(Only used for diagnosis 1)
Set
Judgment Value
Malfunction Criteria Threshold Value
|Crankshaft position when camshaft position sensor signal is input – Learning
value|
> 10°CA
Judgment Value
Malfunction Criteria Threshold Value
Camshaft position sensor signal input position < 78°CA
or
> 137°CA
15WRX_STI_US_EN.book 21 ペー   
GD(w/o STI)-22
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
S: DTC P0018 CRANKSHAFT POSITION - CAMSHAFT POSITION CORRELA-
TION (BANK2)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0016. <Ref. to GD(w/o STI)-20, DTC P0016 CRANKSHAFT PO-
SITION - CAMSHAFT POSITION CORRELATION (BANK1), Diagnostic Trouble Code (DTC) Detecting Cri-
teria.>
T: DTC P0019 CRANK AND CAM TIMING B SYSTEM FAILURE (BANK 2)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0017. <Ref. to GD(w/o STI)-21, DTC P0017 CRANK AND CAM
TIMING B SYSTEM FAILURE (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>
U: DTC P0020 "A" CAMSHAFT POSITION ACTUATOR CIRCUIT/OPEN (BANK
2)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0010. <Ref. to GD(w/o STI)-15, DTC P0010 "A" CAMSHAFT PO-
SITION ACTUATOR CIRCUIT/OPEN (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>
V: DTC P0021 INTAKE CAMSHAFT POSITION - TIMING OVER-ADVANCED OR
SYSTEM PERFORMANCE (BANK 2)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0011. <Ref. to GD(w/o STI)-16, DTC P0011 INTAKE CAMSHAFT
POSITION - TIMING OVER-ADVANCED OR SYSTEM PERFORMANCE (BANK 1), Diagnostic Trouble
Code (DTC) Detecting Criteria.>
W: DTC P0023 B CAMSHAFT POSITION ACTUATOR CIRCUIT/OPEN (BANK 2)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0013. <Ref. to GD(w/o STI)-18, DTC P0013 B CAMSHAFT PO-
SITION ACTUATOR CIRCUIT/OPEN (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>
X: DTC P0024 EXHAUST AVCS SYSTEM 2 (RANGE/PERFORMANCE)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0014. <Ref. to GD(w/o STI)-19, DTC P0014 EXHAUST AVCS
SYSTEM 1 (RANGE/PERFORMANCE), Diagnostic Trouble Code (DTC) Detecting Criteria.>
Y: DTC P0030 HO2S HEATER CONTROL CIRCUIT (BANK 1 SENSOR 1)
1. OUTLINE OF DIAGNOSIS
Detect functional errors of the front oxygen (A/F) sensor heater.
Judge as NG when it is determined that the front oxygen (A/F) sensor impedance is large when looking at en-
gine status such as deceleration fuel cut.
15WRX_STI_US_EN.book 22 ペー   
GD(w/o STI)-23
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis continuously after starting the engine.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 25 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(1) Element cover (outer) (2) Element cover (inner) (3) Sensor element
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
A/F sensor heater duty > 21%
Judgment Value
Malfunction Criteria Threshold Value
Front oxygen (A/F) sensor impedance > 100 Ω
(2)
EN-10461
(3)
(1)
15WRX_STI_US_EN.book 23 ペー   
GD(w/o STI)-24
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
Z: DTC P0031 HO2S HEATER CONTROL CIRCUIT LOW (BANK 1 SENSOR 1)
1. OUTLINE OF DIAGNOSIS
Detect front oxygen (A/F) sensor heater open or short circuit.
The front oxygen (A/F) sensor heater performs duty control, and the output terminal voltage at ON is 0 V, and
the output terminal voltage at OFF is the battery voltage.
Judge as NG when the terminal voltage remains Low.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 1000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Front oxygen (A/F) sensor heater control duty 80%
Judgment Value
Malfunction Criteria Threshold Value
Output voltage 2.2 V
15WRX_STI_US_EN.book 24 ペー   
GD(w/o STI)-25
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AA:DTC P0032 HO2S HEATER CONTROL CIRCUIT HIGH (BANK 1 SENSOR 1)
1. OUTLINE OF DIAGNOSIS
Detect front oxygen (A/F) sensor heater open or short circuit.
The front oxygen (A/F) sensor heater performs duty control, and the output terminal voltage at ON is 0 V, and
the output terminal voltage at OFF is the battery voltage.
Judge as NG when overcurrent is detected.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2250 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Front oxygen (A/F) sensor heater control duty 20%
Judgment Value
Malfunction Criteria Threshold Value
Output current 17 A
15WRX_STI_US_EN.book 25 ペー   
GD(w/o STI)-26
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AB:DTC P0037 HO2S HEATER CONTROL CIRCUIT LOW (BANK 1 SENSOR 2)
1. OUTLINE OF DIAGNOSIS
Detect the rear oxygen sensor heater open or short circuit.
The rear oxygen sensor heater performs duty control, and the output terminal voltage at ON is 0 V, and the
output terminal voltage at OFF is the battery voltage.
Judge as NG when the terminal voltage remains Low.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2500 ms
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Rear oxygen sensor heater control duty 96%
Judgment Value
Malfunction Criteria Threshold Value
Output voltage 2.2 V
15WRX_STI_US_EN.book 26 ペー   
GD(w/o STI)-27
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AC:DTC P0038 HO2S HEATER CONTROL CIRCUIT HIGH (BANK 1 SENSOR 2)
1. OUTLINE OF DIAGNOSIS
Detect the rear oxygen sensor heater open or short circuit.
The rear oxygen sensor heater performs duty control, and the output terminal voltage at ON is 0 V, and the
output terminal voltage at OFF is the battery voltage.
Judge as NG when overcurrent is detected.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2500 ms
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Rear oxygen sensor heater control duty 4%
Judgment Value
Malfunction Criteria Threshold Value
Output current 17 A
15WRX_STI_US_EN.book 27 ペー   
GD(w/o STI)-28
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AD:DTC P0068 MAP/MAF - THROTTLE POSITION CORRELATION
1. OUTLINE OF DIAGNOSIS
Detect problems in the manifold absolute pressure sensor output properties.
Judge as NG when the intake air pressure AD value is Low whereas it seemed to be High from the viewpoint
of engine condition, or when it is High whereas it seemed to be Low from the engine condition.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis continuously after idling.
(1) Manifold absolute pressure sensor (2) Voltage (V) (3) Absolute pressure (kPa)
Low
Secondary Parameters Enable Conditions
Engine coolant temperature 55°C (131°F)
Engine speed < 3600 rpm
Charging efficiency 35%
Throttle position 8.9%
High
Secondary Parameters Enable Conditions
Engine coolant temperature 55°C (131°F)
Engine speed 475 rpm
and
< 950 rpm
Charging efficiency 30%
Throttle position 4.8%
EN-10452
(2)
(3)
(1)
15WRX_STI_US_EN.book 28 ペー   
GD(w/o STI)-29
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
Judge as NG when Low side or High side becomes NG.
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis:
Low side: 5000 ms
High side: 5000 ms
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
Low
Intake manifold pressure (absolute pressure) < 30 kPa (225 mmHg, 8.9 inHg)
High
Intake manifold pressure (absolute pressure) 100 kPa (750.1 mmHg, 29.5 inHg)
15WRX_STI_US_EN.book 29 ペー   
GD(w/o STI)-30
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AE:DTC P0071 AMBIENT TEMPERATURE SENSOR CIRCUIT "A" RANGE/PER-
FORMANCE
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of ambient temperature sensor characteristics.
After the engine starts after the specified period of soaking time has elapsed, judge by correlation between
ambient temperature sensor value, intake air temperature sensor value and engine coolant temperature sen-
sor value. Judge as NG when the differences are both above the specified value by comparing between am-
bient air temperature and intake air temperature, ambient air temperature and engine coolant temperature.
2. COMPONENT DESCRIPTION
Ambient temperature sensor is connected to combination meter. ECM receives the data of ambient temper-
ature sensor via CAN communication with combination meter.
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis only once after the engine starts after a certain period of soaking time.
(1) Ambient temperature sensor (2) Resistance value (kΩ) (3) Ambient air temperature (°C (°F))
Secondary Parameters Enable Conditions
Soaking time 21600 s
Block heater judgment Completed
Block heater operation Not in operation
EN-10816
(2)
(3)
(1)
15WRX_STI_US_EN.book 30 ペー   
GD(w/o STI)-31
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
|Ambient air temperature 30 sec. after engine start – Intake air temperature 30 sec. after engine start| > Value from Map
|Ambient air temperature at engine start – Engine coolant temperature at engine start| > 25°C (45°F)
Map
Ambient air temperature
°C (°F)
–30
(–22)
30
(86)
45
(113)
60
(140)
|Ambient air temperature 30 sec. after engine start – Intake
air temperature 30 sec. after engine start|
°C (°F)
20
(36)
20
(36)
32
(57.6)
32
(57.6)
15WRX_STI_US_EN.book 31 ペー   
GD(w/o STI)-32
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AF:DTC P0072 AMBIENT TEMPERATURE SENSOR CIRCUIT "A" LOW
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of ambient temperature sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
Ambient temperature sensor is connected to combination meter. ECM receives the data of ambient temper-
ature sensor via CAN communication with combination meter.
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously after the enable conditions have been established.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2.56 seconds
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Ambient temperature sensor (2) Resistance value (kΩ) (3) Ambient air temperature (°C (°F))
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
Output voltage < 0.42 V
EN-10816
(2)
(3)
(1)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AG:DTC P0073 AMBIENT TEMPERATURE SENSOR CIRCUIT "A" HIGH
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of ambient temperature sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
Ambient temperature sensor is connected to combination meter. ECM receives the data of ambient temper-
ature sensor via CAN communication with combination meter.
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously after the enable conditions have been established.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2.56 seconds
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
AH:DTC P0087 FUEL RAIL/SYSTEM PRESSURE - TOO LOW
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0088. <Ref. to GD(w/o STI)-34, DTC P0088 FUEL RAIL/SYSTEM
PRESSURE - TOO HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>
(1) Ambient temperature sensor (2) Resistance value (kΩ) (3) Ambient air temperature (°C (°F))
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
Output voltage > 4.88 V
EN-10816
(2)
(3)
(1)
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GD(w/o STI)-34
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AI: DTC P0088 FUEL RAIL/SYSTEM PRESSURE - TOO HIGH
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of high pressure fuel system function.
Judge as NG when actual pressure is not close to target pressure.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 10 seconds
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Continuous time after fuel cut > 3 s
Target pressure change every 10 ms 500 kPa (3750.3 mmHg, 147.7 inHg)
Judgment Value
Malfunction Criteria Threshold Value DTC
Target fuel pressure – Actual fuel pressure > 3300 kPa (24752.1 mmHg, 974.5 inHg) P0087
Actual fuel pressure – Target fuel pressure > 6000 kPa (45003.8 mmHg, 1771.8 inHg) P0088
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AJ:DTC P0096 INTAKE AIR TEMPERATURE SENSOR #2 RANGE/PERFOR-
MANCE PROBLEM
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of the intake air temperature sensor (integrated with manifold absolute pressure sen-
sor) output properties. Using the following two diagnoses, judge as NG when either is NG.
Diagnosis 1 (correlation diagnosis): After the engine starts after the specified period of soaking time has
elapsed, diagnose by correlation between intake air temperature sensor value, engine coolant temperature
sensor value and ambient temperature sensor value. Judge as NG when the differences are both above the
specified value by comparing between intake air temperature and engine coolant temperature, intake air
temperature and ambient air temperature.
Diagnosis 2 (stuck diagnosis): Judge as NG when intake air temperature does not change under the
driving condition where it should change, considering engine condition.
2. COMPONENT DESCRIPTION
Intake air temperature sensor (integrated with manifold absolute pressure sensor)
3. ENABLE CONDITIONS
(1) Intake air temperature sensor (2) Resistance value (Ω) (3) Intake air temperature °C (°F)
Diagnosis 1
Secondary Parameters Enable Conditions
Soaking time 21600 s
Block heater judgment Completed
Block heater operation Not in operation
Diagnosis 2
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Engine coolant temperature 60°C (140°F)
Intake air amount sum value 6,500 g
Number of experiences under conditions below 3 times
• Continuous time when vehicle speed is less than 4 km/h (2.5 MPH) 24 s
•Continuous time when the vehicle speed is 40 km/h (24.9 MPH) or more, and
intake air amount is 10 g/s (0.4 oz/s) or more
10 s
EN-10450
(3)
(2)
(1)
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GD(w/o STI)-36
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
4. GENERAL DRIVING CYCLE
Diagnosis 1: Perform the diagnosis only once after the engine starts after a certain period of soaking time.
Diagnosis 2: Perform the diagnosis when the vehicle speed condition is met after warming up from a cold
condition.
5. DIAGNOSTIC METHOD
Judge as NG when Diagnosis 1 or Diagnosis 2 becomes NG.
Diagnosis 1
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: Less than 1 second
Diagnosis 2
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
|Intake air temperature (manifold absolute pressure sensor) 30 sec. after engine
start – Intake air temperature (air flow sensor) 30 sec. after engine start|
> Value of Map 1
|Intake air temperature (manifold absolute pressure sensor) 30 sec. after engine
start – Ambient air temperature 30 sec. after engine start|
> Value of Map 2
Map 1
Ambient air temperature
°C (°F)
–30
(–22)
30
(86)
45
(113)
60
(140)
|Intake air temperature (manifold absolute pressure sensor)
30 sec. after engine start – Intake air temperature (air flow
sensor) 30 sec. after engine start|
°C (°F)
11
(19.8)
11
(19.8)
11
(19.8)
11
(19.8)
Map 2
Ambient air temperature
°C (°F)
–30
(–22)
30
(86)
45
(113)
60
(140)
|Intake air temperature (manifold absolute pressure sensor)
30 sec. after engine start – Ambient air temperature 30 sec.
after engine start|
°C (°F)
20
(36)
20
(36)
32
(57.6)
32
(57.6)
Judgment Value
Malfunction Criteria Threshold Value
Output voltage difference between Max. and Min. < 0.02 V (Equivalent to approximately 0.5°C (0.9°F) near 25°C (77°F))
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AK:DTC P0097 INTAKE AIR TEMPERATURE SENSOR #2 CIRCUIT (LOW)
1. OUTLINE OF DIAGNOSIS
Detect open or short circuit of the intake air temperature sensor (integrated with manifold absolute pressure
sensor).
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 520 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Intake air temperature sensor (2) Resistance value (kΩ) (3) Intake air temperature (°C (°F))
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage < 0.22 V
EN-10450
(3)
(2)
(1)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AL:DTC P0098 INTAKE AIR TEMPERATURE SENSOR #2 CIRCUIT (HIGH)
1. OUTLINE OF DIAGNOSIS
Detect open or short circuit of the intake air temperature sensor (integrated with manifold absolute pressure
sensor).
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 520 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Intake air temperature sensor (2) Resistance value (kΩ) (3) Intake air temperature (°C (°F))
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage > 4.72 V
EN-10450
(3)
(2)
(1)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AM:DTC P0101 MASS OR VOLUME AIR FLOW CIRCUIT RANGE/PERFOR-
MANCE
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of air flow sensor output properties.
Judge as a low side NG when the air flow voltage indicates a small value regardless of running in a state
where the air flow voltage increases. Judge as a high side NG when the air flow voltage indicates a large val-
ue regardless of running in a state where the air flow voltage decreases. Judge air flow sensor property NG
when the Low side or High side becomes NG.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
(A) Air
(1) Air flow sensor (2) Voltage (V) (3) Intake air amount (g (oz)/s)
Low
Secondary Parameters Enable Conditions
Engine speed 1500 rpm
Throttle position 12.6%
Engine coolant temperature 60°C (140°F)
Intake manifold pressure 90 kPa (675.1 mmHg, 26.6 inHg)
High
Secondary Parameters Enable Conditions
Engine speed 475 rpm
and
< 915 rpm
Throttle position < 6.3%
Engine coolant temperature 60°C (140°F)
Intake manifold pressure < 64 kPa (480 mmHg, 18.9 inHg)
(2)
(3)
EN-10451
(A)
(1)
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GD(w/o STI)-40
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
4. GENERAL DRIVING CYCLE
Perform the diagnosis continuously after idling.
5. DIAGNOSTIC METHOD
Judge as NG when Low side or High side becomes NG.
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis:
Low: 5 s
High: 10 s
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
Low
Output voltage < 1.05 V
High
Output voltage 1.75 V
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AN:DTC P0102 MASS OR VOLUME AIR FLOW CIRCUIT LOW INPUT
1. OUTLINE OF DIAGNOSIS
Detect open or short circuits of the air flow sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 520 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Air
(1) Air flow sensor (2) Voltage (V) (3) Intake air amount (g (oz)/s)
Secondary Parameters Enable Conditions
Elapsed time after ignition switch is turned to ON < 1040 ms
Judgment Value
Malfunction Criteria Threshold Value
Output voltage < 0.12 V
(2)
(3)
EN-10451
(A)
(1)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AO:DTC P0103 MASS OR VOLUME AIR FLOW CIRCUIT HIGH INPUT
1. OUTLINE OF DIAGNOSIS
Detect open or short circuits of the air flow sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 520 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Air
(1) Air flow sensor (2) Voltage (V) (3) Intake air amount (g (oz)/s)
Secondary Parameters Enable Conditions
Elapsed time after ignition switch is turned to ON 1040 ms
Judgment Value
Malfunction Criteria Threshold Value
Output voltage > 4.79 V
(2)
(3)
EN-10451
(A)
(1)
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GD(w/o STI)-43
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AP:DTC P0107 MANIFOLD ABSOLUTE PRESSURE/BAROMETRIC PRESSURE
CIRCUIT LOW INPUT
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of manifold absolute pressure sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Manifold absolute pressure sensor (2) Voltage (V) (3) Absolute pressure (kPa)
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage < 0.36 V
EN-10452
(2)
(3)
(1)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AQ:DTC P0108 MANIFOLD ABSOLUTE PRESSURE/BAROMETRIC PRESSURE
CIRCUIT HIGH INPUT
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of manifold absolute pressure sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Manifold absolute pressure sensor (2) Voltage (V) (3) Absolute pressure (kPa)
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage > 4.85 V
EN-10452
(2)
(3)
(1)
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GD(w/o STI)-45
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AR:DTC P0111 INTAKE AIR TEMPERATURE SENSOR RANGE/PERFORMANCE
PROBLEM
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of the intake air temperature sensor (integrated with air flow sensor) output properties.
Using the following two diagnoses, judge as NG when either is NG.
Diagnosis 1 (correlation diagnosis): After the engine starts after the specified period of soaking time has
elapsed, diagnose by correlation between intake air temperature sensor value, engine coolant temperature
sensor value and ambient temperature sensor value. Judge as NG when the differences are both above the
specified value by comparing between intake air temperature and engine coolant temperature, intake air
temperature and ambient air temperature.
Diagnosis 2 (stuck diagnosis): Judge as NG when intake air temperature does not change under the
driving condition where it should change, considering engine condition.
2. COMPONENT DESCRIPTION
Intake air temperature sensor (integrated with air flow sensor)
(A) Air
(1) Intake air temperature sensor (2) Resistance value (Ω) (3) Intake air temperature °C (°F)
(2)
(3)
EN-10453
(A)
(1)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Diagnosis 1: Perform the diagnosis only once after the engine starts after a certain period of soaking time.
Diagnosis 2: Perform the diagnosis when the vehicle speed condition is met after warming up from a cold
condition.
Diagnosis 1
Secondary Parameters Enable Conditions
Soaking time 21600 s
Block heater judgment Completed
Block heater operation Not in operation
Diagnosis 2
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Engine coolant temperature 60°C (140°F)
Intake air amount sum value 6,500 g
Number of experiences under conditions below 3 times
• Continuous time when vehicle speed is less than 4 km/h (2.5 MPH) 24 s
•Continuous time when the vehicle speed is 40 km/h (24.9 MPH) or more, and
intake air amount is 10 g/s (0.4 oz/s) or more
10 s
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GD(w/o STI)-47
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
Judge as NG when Diagnosis 1 or Diagnosis 2 becomes NG.
Diagnosis 1
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: Less than 1 second
Diagnosis 2
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
|Intake air temperature (air flow sensor) 30 sec. after engine start – Engine cool-
ant temperature at engine start|
> Value of Map 1
|Intake air temperature (air flow sensor) 30 sec. after engine start – Ambient air
temperature 30 sec. after engine start|
> Value of Map 2
Map 1
Ambient air temperature
°C (°F)
–30
(–22)
30
(86)
45
(113)
60
(140)
|Intake air temperature (air flow sensor) 30 sec. after engine
start – Engine coolant temperature at engine start|
°C (°F)
12
(21.6)
12
(21.6)
22
(39.6)
22
(39.6)
Map 2
Ambient air temperature
°C (°F)
–30
(–22)
30
(86)
45
(113)
60
(140)
|Intake air temperature (air flow sensor) 30 sec. after engine
start – Ambient air temperature 30 sec. after engine start|
°C (°F)
20
(36)
20
(36)
32
(57.6)
32
(57.6)
Judgment Value
Malfunction Criteria Threshold Value
Output voltage difference between Max. and Min. < 0.02 V (Equivalent to approximately 0.5°C (0.9°F) near 25°C (77°F))
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AS:DTC P0112 INTAKE AIR TEMPERATURE SENSOR 1 CIRCUIT LOW
1. OUTLINE OF DIAGNOSIS
Detect open or short circuit of the intake air temperature sensor (integrated with air flow sensor).
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 520 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Air
(1) Intake air temperature sensor (2) Resistance value (Ω) (3) Intake air temperature °C (°F)
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage < 0.22 V
(2)
(3)
EN-10453
(A)
(1)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AT:DTC P0113 INTAKE AIR TEMPERATURE SENSOR 1 CIRCUIT HIGH
1. OUTLINE OF DIAGNOSIS
Detect open or short circuit of the intake air temperature sensor (integrated with air flow sensor).
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 520 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Air
(1) Intake air temperature sensor (2) Resistance value (Ω) (3) Intake air temperature °C (°F)
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage > 4.72 V
(2)
(3)
EN-10453
(A)
(1)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AU:DTC P0116 ENGINE COOLANT TEMPERATURE SENSOR 1 CIRCUIT
RANGE/PERFORMANCE
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of the engine coolant temperature sensor characteristics.
After the engine starts after the specified period of soaking time has elapsed, diagnose by correlation be-
tween engine coolant temperature sensor value, intake air temperature sensor value and ambient tempera-
ture sensor value. Judge as NG when the differences are both above the specified value by comparing
between engine coolant temperature and ambient air temperature, engine coolant temperature and intake air
temperature.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis only once after the engine starts after a certain period of soaking time.
(A) Resistance value (kΩ) (B) Temperature °C (°F)
(1) Connector (2) Thermistor element
Secondary Parameters Enable Conditions
Soaking time 21600 s
Block heater judgment Completed
Block heater operation Not in operation
EN-02917
(A)
(2)
(1)
(B)
15WRX_STI_US_EN.book 50 ペー   
GD(w/o STI)-51
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
|Engine coolant temperature at engine start – Intake air temperature 30 sec. after engine start| > Value from Map
|Engine coolant temperature at engine start – Ambient air temperature at engine start| > 25°C (45°F)
Map
Ambient air temperature
°C (°F)
–30
(–22)
30
(86)
45
(113)
60
(140)
|Engine coolant temperature at engine start – Intake air tem-
perature 30 sec. after engine start|
°C (°F)
12
(21.6)
12
(21.6)
22
(39.6)
22
(39.6)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AV:DTC P0117 ENGINE COOLANT TEMPERATURE CIRCUIT LOW
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of the engine coolant temperature sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 500 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Resistance value (kΩ) (B) Temperature °C (°F)
(1) Connector (2) Thermistor element
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage < 0.33 V
EN-02917
(A)
(2)
(1)
(B)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AW:DTC P0118 ENGINE COOLANT TEMPERATURE CIRCUIT HIGH
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of the engine coolant temperature sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 500 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Resistance value (kΩ) (B) Temperature °C (°F)
(1) Connector (2) Thermistor element
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage > 4.71 V
EN-02917
(A)
(2)
(1)
(B)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AX:DTC P0122 THROTTLE/PEDAL POSITION SENSOR/SWITCH “A” CIRCUIT
LOW
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of throttle position sensor 1.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 100 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Throttle position sensor 1 signal (3) Throttle position sensor (4) Engine control module (ECM)
(2) Throttle position sensor 2 signal
Secondary Parameters Enable Conditions
Battery voltage 6 V
Judgment Value
Malfunction Criteria Threshold Value
Sensor 1 input voltage < 0.29 V
EN-10493
(1)
(2)
(3)
(4)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AY:DTC P0123 THROTTLE/PEDAL POSITION SENSOR/SWITCH “A” CIRCUIT
HIGH
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of throttle position sensor 1.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 100 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Throttle position sensor 1 signal (3) Throttle position sensor (4) Engine control module (ECM)
(2) Throttle position sensor 2 signal
Secondary Parameters Enable Conditions
Battery voltage 6 V
Judgment Value
Malfunction Criteria Threshold Value
Sensor 1 input voltage > 4.69 V
EN-10493
(1)
(2)
(3)
(4)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
AZ:DTC P0125 INSUFFICIENT COOLANT TEMPERATURE FOR CLOSED LOOP
FUEL CONTROL
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of engine coolant temperature output property.
Judge as NG when engine coolant temperature does not rise to the specified value after predetermined time
has elapsed since engine start.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis only once after starting the engine from cold condition.
(A) Resistance value (kΩ) (B) Temperature °C (°F)
(1) Connector (2) Thermistor element
Secondary Parameters Enable Conditions
Engine coolant temperature at engine start < –15°C (5°F)
Engine speed > 475 rpm
EN-02917
(A)
(2)
(1)
(B)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 120 or 300 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
Engine coolant temperature < –15°C (5°F)
Elapsed time after starting the engine
((Smaller value either one of engine coolant temperature and intake air tempera-
ture at engine start) –23.3°C (–9.9°F))
120 s
or
Elapsed time after starting the engine
((Smaller value either one of engine coolant temperature and intake air tempera-
ture at engine start) < –23.3°C (–9.9°F))
300 s
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BA:DTC P0128 COOLANT THERMOSTAT (ENGINE COOLANT TEMPERATURE
BELOW THERMOSTAT REGULATING TEMPERATURE)
1. OUTLINE OF DIAGNOSIS
Detect malfunctions of the thermostat function.
Judge as NG when any one of the following conditions is established.
When the actual engine coolant temperature does not reach the maximum temperature necessary to per-
form other OBDII diagnosis and Σ (Estimated engine coolant temperature – actual engine coolant tempera-
ture) exceeded the predetermined value. (Judgment 1)
When the actual engine coolant temperature does not reach the range within –11°C (–19.8°F) from the
regulated temperature and Σ (Estimated engine coolant temperature – actual engine coolant temperature)
exceeded the predetermined value. (Judgment 2)
When the difference between the estimated coolant temperature and the actual engine coolant tempera-
ture exceeds the predetermined value, and Σ (Estimated engine coolant temperature – actual engine coolant
temperature) exceeded the predetermined value. (Judgment 3)
2. COMPONENT DESCRIPTION
(1) Jiggle valve (5) Dust seal (9) Bypass spring
(2) Piston (6) Main spring (10) Bypass valve
(3) Flange (7) Wax element (11) Stop ring
(4) Stop ring (8) Frame
(11)
(10)
(9)
(8)
(7)
(2)
(1)
(3)
(4)
(5)
(6)
EN-08985
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis only once after starting the engine.
Secondary Parameters Enable Conditions
<Judgment 1>
Battery voltage 10.9 V
Estimate ambient temperature –7°C (19.4°F)
Vehicle speed 30 km/h (18.6 MPH)
Estimated coolant temperature > 60°C (140°F)
Coolant temperature at engine starting < 60°C (140°F)
<Judgment 2>
Battery voltage 10.9 V
Estimate ambient temperature –7°C (19.4°F)
Vehicle speed 30 km/h (18.6 MPH)
Estimated coolant temperature > Value of Map 1
Coolant temperature at engine starting < 60°C (140°F)
<Judgment 3>
Battery voltage 10.9 V
Estimate ambient temperature –7°C (19.4°F)
Vehicle speed 30 km/h (18.6 MPH)
Estimated coolant temperature Value from Map 2
Coolant temperature at engine starting < 60°C (140°F)
Map 1
Engine coolant temperature at engine starting
°C (°F)
–7
(19.4)
8
(46.4)
10
(50)
25
(77)
Estimated coolant temperature
°C (°F)
70.6
(159.1)
78.1
(172.6)
78.1
(172.6)
78.1
(172.6)
Map 2
Engine coolant temperature at engine starting
°C (°F)
–7
(19.4)
10
(50)
25
(77)
31.8
(89.2)
Estimated coolant temperature
°C (°F)
55
(131)
65.1
(149.2)
74
(165.2)
78.1
(172.6)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
When any one of the followings is established:
<Judgment 1>
Actual engine coolant temperature < 60°C (140°F)
and
Σ (Estimated engine coolant temperature – actual engine coolant temperature) > Value of Map 3
<Judgment 2>
Actual engine coolant temperature < Regulated temperature – Value of Map 4
and
Σ (Estimated engine coolant temperature – actual engine coolant temperature) > Value of Map 5
<Judgment 3>
Estimated engine coolant temperature – actual engine coolant temperature > 11.1°C (20°F)
and
Σ (Estimated engine coolant temperature – actual engine coolant temperature) > Value of Map 6
Map 3
Engine coolant temperature at
engine starting
°C (°F)
–7
(19.4)
0
(32)
10
(50)
25
(77)
30
(86)
40
(104)
Threshold Value
°C (°F)
1387.5
(2497.5)
1387.5
(2497.5)
1387.5
(2497.5)
1387.5
(2497.5)
1387.5
(2497.5)
961.5
(1730.7)
Map 4
Estimate ambient temperature
°C (°F)
–7
(19.4)
8
(46.4)
10
(50)
25
(77)
Threshold Value
°C (°F)
18.6
(33.5)
11.1
(20)
11.1
(20)
11.1
(20)
Map 5
Engine coolant temperature at
engine starting
°C (°F)
–7
(19.4)
0
(32)
8
(46.4)
10
(50)
30
(86)
35
(95)
Threshold Value
°C (°F)
1387.5
(2497.5)
1387.5
(2497.5)
1387.5
(2497.5)
1387.5
(2497.5)
1387.5
(2497.5)
1201.9
(2163.4)
Map 6
Engine coolant temperature at engine starting
°C (°F)
–7
(19.4)
8
(46.4)
10
(50)
25
(77)
Threshold Value
°C (°F)
1387.5
(2497.5)
1387.5
(2497.5)
1387.5
(2497.5)
1387.5
(2497.5)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BB:DTC P0130 O2 SENSOR CIRCUIT (BANK 1 SENSOR 1)
1. OUTLINE OF DIAGNOSIS
Judge as NG, while the element impedance is low with the element current out of the range.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 3040 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Electromotive force (B) Air fuel ratio (C) Rich
(D) Lean
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Engine speed 500 rpm
Front oxygen (A/F) sensor impedance 403 Ω
Judgment Value
Malfunction Criteria Threshold Value
Input current < –45 µA
or
> 45 µA
EN-10446
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BC:DTC P0131 O2 SENSOR CIRCUIT LOW VOLTAGE (BANK 1 SENSOR 1)
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of sensor.
Judge as NG, when the element voltage is out of the specified range.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 560 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Electromotive force (B) Air fuel ratio (C) Rich
(D) Lean
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Engine speed 500 rpm
Judgment Value
Malfunction Criteria Threshold Value
Input voltage (+) 1 V
or
Input voltage (–) 1 V
or
Sensor reference voltage 1 V
EN-10446
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BD:DTC P0132 O2 SENSOR CIRCUIT HIGH VOLTAGE (BANK 1 SENSOR 1)
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of sensor.
Judge as NG, when the element voltage is out of the specified range.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 560 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Electromotive force (B) Air fuel ratio (C) Rich
(D) Lean
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Engine speed 500 rpm
Judgment Value
Malfunction Criteria Threshold Value
Input voltage (+) Battery voltage – 1 V
or
Input voltage (–) Battery voltage – 1 V
or
Sensor reference voltage 6.5 V
EN-10446
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BE:DTC P0134 O2 SENSOR CIRCUIT NO ACTIVITY DETECTED (BANK 1 SEN-
SOR 1)
1. OUTLINE OF DIAGNOSIS
Detect open circuits of the sensor.
Judge as NG when the element voltage is out of range, or the element current is stuck.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
(A) Electromotive force (B) Air fuel ratio (C) Rich
(D) Lean
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Engine speed 500 rpm
<When out of range>
Front oxygen (A/F) sensor impedance
> 403 Ω
<When stuck>
Front oxygen (A/F) sensor impedance
403 Ω
EN-10446
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis:
Input voltage (+): 30000 ms
Sensor reference voltage: 2000 ms
Input current: 2000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Judgment Value
Malfunction Criteria Threshold Value
Input voltage (+) > 2.65 V
or
Sensor reference voltage 3.6 V
or
Input current –45 µA — 45 µA
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BF:DTC P0137 O2 SENSOR CIRCUIT LOW VOLTAGE (BANK 1 SENSOR 2)
1. OUTLINE OF DIAGNOSIS
Detect continuity NG of the oxygen sensor. Judge as NG when the oxygen sensor voltage reading is not with-
in the probable range.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously after the enable conditions have been established.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 1 second
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) Electromotive force (B) Air fuel ratio (C) Lean
(D) Rich (E) Theoretical air fuel ratio (F) Comparative voltage
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
Oxygen sensor offset voltage < 1.7 V
EN-10447
(E)
(F)
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BG:DTC P0138 O2 SENSOR CIRCUIT HIGH VOLTAGE (BANK 1 SENSOR 2)
1. OUTLINE OF DIAGNOSIS
Detect continuity NG of the oxygen sensor. Judge as NG when the oxygen sensor voltage reading is not with-
in the probable range.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously after the enable conditions have been established.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 1 second
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) Electromotive force (B) Air fuel ratio (C) Lean
(D) Rich (E) Theoretical air fuel ratio (F) Comparative voltage
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
Oxygen sensor offset voltage > 2.3 V
or
Oxygen sensor voltage > 3.3 V
EN-10447
(E)
(F)
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BH:DTC P013A O2 SENSOR SLOW RESPONSE - RICH TO LEAN (BANK 1 SEN-
SOR 2)
1. OUTLINE OF DIAGNOSIS
Detect the slow response of rich lean for rear oxygen sensor output.
When the deceleration fuel cut has occurred, detect the trouble by calculating the time when the rear oxygen
sensor output passes through the predetermined range of voltages.
Judge as NG when the response time is larger than the threshold value.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform diagnosis once during deceleration fuel cut from a constant and high speed driving, when rear oxy-
gen sensor is warmed up sufficiently.
(A) Electromotive force (B) Air fuel ratio (C) Lean
(D) Rich (E) Theoretical air fuel ratio (F) Comparative voltage
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Current calculation time of the rear oxygen sensor heater after starting 180000 ms
Rear oxygen sensor voltage when fuel cut starts 0.55 V
Fuel cut In operation
Estimated temperature of rear oxygen sensor element when fuel cut starts 450°C (842°F)
EN-10447
(E)
(F)
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
Detect the trouble by calculating the response time of the rear oxygen sensor during fuel cut.
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 5 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) 0.55 V (B) 0.50 V (C) 0.20 V
(D) 0.15 V (E) 0 V (F) Diagnostic parameter
(G) Normal (H) Malfunction
Judgment Value
Malfunction Criteria Threshold Value
Time needed for rear oxygen sensor voltage to change from 0.5 V to 0.2 V > 837 ms
EN-09344
(H)
(E)
(D)
(C)
(B)
(A)
Rear oxygen sensor (V)
Fuel cut on deceleration
(F)
(G)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BI: DTC P013B O2 SENSOR SLOW RESPONSE - LEAN TO RICH (BANK 1 SEN-
SOR 2)
1. OUTLINE OF DIAGNOSIS
Detect the slow response of lean rich for rear oxygen sensor output.
After the deceleration fuel cut has occurred, detect the trouble by calculating the time when the rear oxygen
sensor output passes through the predetermined range of voltages.
Judge as NG when the response time is larger than the threshold value.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform diagnosis only once after recovering from a deceleration fuel cut continued for more than predeter-
mined time.
(A) Electromotive force (B) Air fuel ratio (C) Lean
(D) Rich (E) Theoretical air fuel ratio (F) Comparative voltage
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Main feedback In operation
Deceleration fuel cut of 5000 ms or more Experienced
EN-10447
(E)
(F)
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
Detect the trouble by calculating the response time of the rear oxygen sensor after fuel cut.
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 4 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) 0.55 V (B) 0.50 V (C) 0.30 V
(D) 0.25 V (E) 0 V (F) Diagnostic parameter
(G) Normal (H) Malfunction
Judgment Value
Malfunction Criteria Threshold Value
Time when rear oxygen sensor voltage changed from 0.3 V to 0.5 V > 4000 ms
(H)
(D)
(C)
EN-09345
(E)
(B)
(A)
Rear oxygen sensor (V)
Fuel cut on deceleration
(F)
(G)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BJ:DTC P013E O2 SENSOR DELAYED RESPONSE - RICH TO LEAN (BANK 1
SENSOR 2)
1. OUTLINE OF DIAGNOSIS
Detect the delayed response of rear oxygen sensor output for rich lean.
After the deceleration fuel cut has started, detect the trouble by calculating the time when the rear oxygen
sensor output decreases to the predetermined voltages.
Judge as NG when the response time is larger than the threshold value.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform diagnosis once during deceleration fuel cut from a constant and high speed driving, when rear oxy-
gen sensor is warmed up sufficiently.
(A) Electromotive force (B) Air fuel ratio (C) Lean
(D) Rich (E) Theoretical air fuel ratio (F) Comparative voltage
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Rear oxygen sensor voltage when fuel cut starts 0.55 V
Fuel cut In operation
Estimated temperature of rear oxygen sensor element when fuel cut starts 450°C (842°F)
Fuel injection increase amount of exhaust system protection = 0
EN-10447
(E)
(F)
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
Detect the trouble by calculating the time from the beginning of the fuel cut to the beginning of the rear oxy-
gen sensor voltage starting to drop.
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 5 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) 0.5 V (B) 0 V (C) Diagnostic parameter
(D) Normal (E) Malfunction
Judgment Value
Malfunction Criteria Threshold Value
Time when rear oxygen sensor voltage changed to 0.5 V after the fuel cut started > 4000 ms
(E)
EN-09346
(B)
(A)
Rear oxygen sensor (V)
Fuel cut on deceleration
(D)
(C)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BK:DTC P013F O2 SENSOR DELAYED RESPONSE - LEAN TO RICH (BANK 1
SENSOR 2)
1. OUTLINE OF DIAGNOSIS
Detect the delayed response of rear oxygen sensor output for lean rich.
After the deceleration fuel cut has completed, detect the trouble by calculating the time when the rear oxygen
sensor output increases to the predetermined voltages.
Judge as NG when the response time is larger than the threshold value.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform diagnosis only once when recovering from the deceleration fuel cut continued for more than prede-
termined time with the rear oxygen sensor warmed up sufficiently.
(A) Electromotive force (B) Air fuel ratio (C) Lean
(D) Rich (E) Theoretical air fuel ratio (F) Comparative voltage
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Main feedback In operation
Rear oxygen sensor voltage when fuel cut has completed 0.15 V
Deceleration fuel cut of 5000 ms or more Experienced
Estimated element temperature of rear oxygen sensor when fuel cut has com-
pleted
450°C (842°F)
EN-10447
(E)
(F)
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
Detect the trouble by calculating the time from the completion of the fuel cut to the beginning of the rear ox-
ygen sensor voltage starting to rise.
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 40 ms × 3000 times
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) 0.3 V (B) 0 V (C) Diagnostic parameter
(D) Normal (E) Malfunction
Judgment Value
Malfunction Criteria Threshold Value
The number of times that the rear oxygen sensor voltage changed to 0.3 V after
the fuel cut has completed (time counter)
> 40 ms × 3000 times
(E)
(A)
EN-09347
(B)
Rear oxygen sensor (V)
Fuel cut on deceleration
(D)
(C)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BL:DTC P0141 O2 SENSOR HEATER CIRCUIT (BANK1 SENSOR2)
1. OUTLINE OF DIAGNOSIS
Detect malfunction of the rear oxygen sensor heater.
Judge as NG if it is determined that the rear oxygen sensor impedance is large by observing the engine con-
ditions.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 10 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(1) Element cover (outer) (3) Sensor element (4) Ceramic heater
(2) Element cover (inner)
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Rear oxygen sensor heater control duty 4%
Judgment Value
Malfunction Criteria Threshold Value
Rear oxygen sensor heater current < Value from Map
Map
Battery voltage (V) 10.9 12 13 14 15 16
Threshold Value (mA) 330 357.5 385 412.5 440 467.5
(4)
(2)
EN-10462
(3)
(1)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BM:DTC P014C O2 SENSOR SLOW RESPONSE - RICH TO LEAN (BANK 1 SEN-
SOR 1)
1. OUTLINE OF DIAGNOSIS
Detect the slow response of front oxygen (A/F) sensor.
For diagnosis, detect the trouble by processing the λ waveform in normal driving without forcibly changing
the target air fuel ratio.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform diagnosis only once in a city driving including normal acceleration and deceleration.
(A) Electromotive force (B) Air fuel ratio (C) Rich
(D) Lean
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Operation time of main feedback 5 s
Engine speed 1000 rpm
Amount of intake air 10 g/s (0.35 oz/s)
EN-10446
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD 1
Detect the malfunction by checking “Cumulative value of time when λ changes from lean rich” in compar-
ison to “Time during which diagnosis is in progress”.
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 120 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) Time during which diagnosis is in
progress
(B) Cumulative value of time when λ
changes from lean rich
Judgment Value
Malfunction Criteria Threshold Value DTC
(Cumulative value of time when λ changes from lean rich) / (Time during which diagno-
sis is in progress)
< 0.38 P014C
> 0.61 P014D
EN-09340
time
Rich
Lean
(Sensor output)
Accumulated time
(B)
(A)
15WRX_STI_US_EN.book 78 ペー   
GD(w/o STI)-79
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
6. DIAGNOSTIC METHOD 2
Detect the malfunction by the cumulative value obtained from the amount of variation in λ change.
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 120 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
BN:DTC P014D O2 SENSOR SLOW RESPONSE - LEAN TO RICH (BANK 1 SEN-
SOR 1)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P014C. <Ref. to GD(w/o STI)-77, DTC P014C O2 SENSOR SLOW
RESPONSE - RICH TO LEAN (BANK 1 SENSOR 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>
(Sensor output)
EN-09341
n-2
n
n-1
Judgment Value
Malfunction Criteria Threshold Value DTC
Cumulative value obtained from the amount of variation in λ change
Σ |(lambda(n) – lambda(n-1)) – (lambda(n-1) – lambda(n-2))|
< Value from Map P014C and P014D
Map
Cumulative value obtained from the amount of variation in λ
Σ |lambda(n) – lambda(n-1)|
0.00 3.00
Cumulative value obtained from the amount of variation in λ change 0.00 2.50
15WRX_STI_US_EN.book 79 ペー   
GD(w/o STI)-80
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BO:DTC P015A O2 SENSOR DELAYED RESPONSE - RICH TO LEAN (BANK 1
SENSOR 1)
1. OUTLINE OF DIAGNOSIS
Detect the slow response of front oxygen (A/F) sensor.
For diagnosis, detect the trouble by processing the λ waveform in normal driving without forcibly changing
the target air fuel ratio.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform diagnosis only once in a city driving including normal acceleration and deceleration.
(A) Electromotive force (B) Air fuel ratio (C) Rich
(D) Lean
Diagnostic method 1 and 2
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Operation time of main feedback 5 s
Engine speed 1000 rpm
Amount of intake air 10 g/s (0.35 oz/s)
DIAGNOSIS METHOD 3 (MT MODEL ONLY)
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Main feedback In operation
Vehicle speed 40 km/h (24.9 MPH)
Engine speed 1000 rpm
and
< 4000 rpm
Amount of intake air 7.5 g/s (0.3 oz/s)
and
< 40 g/s (1.4 oz/s)
Catalyst depletion diagnosis Not under diagnosis
EN-10446
(C) (B) (D)
(A)
15WRX_STI_US_EN.book 80 ペー   
GD(w/o STI)-81
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD 1
Detect the malfunction depending on the average value of time necessary for λ to inverse the air fuel ratio
from “Lean Rich Lean” to “Rich Lean Rich”.
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 100 times of inversion
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value DTC
Average value of time necessary for λ to inverse the air fuel ratio to Lean
Rich Lean
> 100 ms P015A
Average value of time necessary for λ to inverse the air fuel ratio to Rich
Lean Rich
> 110 ms P015B
EN-09342
time
Rich
Lean
(Sensor output)
15WRX_STI_US_EN.book 81 ペー   
GD(w/o STI)-82
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
6. DIAGNOSTIC METHOD 2
Detect the malfunction by calculating the average amplitude of λ.
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 90 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value DTC
Average value for λ amplitude > 0.08 P015A and P015B
EN-09343
time
Rich
Lean
Amplitude
(Sensor output)
15WRX_STI_US_EN.book 82 ペー   
GD(w/o STI)-83
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
7. DIAGNOSIS METHOD 3 (MT MODEL ONLY)
Change STFT (A/F compensation value) by interruption, and measure the reaction time of λ value. When A/
F sensor malfunctions, the reaction time takes longer than at normal condition. In this case, judge as abnor-
mal.
EN-09890
Time
Lean
Rich
Lean
Rich
STFT
Response time
Time
Sensor output
15WRX_STI_US_EN.book 83 ペー   
GD(w/o STI)-84
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
Measure reaction time (t1, t2, t3) and reaction time (t4, t5, t6). Use the average value of the reaction time to
obtain the diagnostic value.
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 4.5 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
BP:DTC P015B O2 SENSOR DELAYED RESPONSE - LEAN TO RICH (BANK 1
SENSOR 1)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P015A. <Ref. to GD(w/o STI)-80, DTC P015A O2 SENSOR DE-
LAYED RESPONSE - RICH TO LEAN (BANK 1 SENSOR 1), Diagnostic Trouble Code (DTC) Detecting Cri-
teria.>
Judgment Value
Malfunction Criteria Threshold Value DTC
(t1 + t2 + t3)/3 > 0.8 s P015A and P015B
and
(t4 + t5 + t6)/3 > 0.8 s
EN-09891
Time
Lean
Rich
Lean
Rich
STFT
Time
Sensor output
t1 t2 t3
t4 t5 t6
15WRX_STI_US_EN.book 84 ペー   
GD(w/o STI)-85
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BQ:DTC P0171 SYSTEM TOO LEAN (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect fuel system malfunction by the amount of main feedback control.
Fuel system is diagnosed by comparing the target air fuel ratio calculated by ECM with the actual air fuel ratio
measured by sensor.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis continuously during main feedback.
4. DIAGNOSTIC METHOD
Compare the diagnostic value with the threshold value, and if a condition meeting the criteria continues for
10 s × 3 times or more, judge that there is a fault in the fuel system.
Time Needed for Diagnosis: 10 s × 3 times
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Secondary Parameters Enable Conditions
Main feedback In operation
Judgment Value
Malfunction Criteria Threshold Value
faf × (1+flaf) > 1.35
faf = Main feedback compensation coefficient
flaf = main feedback learning compensation coefficient
15WRX_STI_US_EN.book 85 ペー   
GD(w/o STI)-86
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BR:DTC P0172 SYSTEM TOO RICH (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect fuel system malfunction by the amount of main feedback control.
Fuel system is diagnosed by comparing the target air fuel ratio calculated by ECM with the actual air fuel ratio
measured by sensor.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis continuously after idling.
4. DIAGNOSTIC METHOD
Compare the diagnostic value with the threshold value, and if a condition meeting the criteria continues for
10 s × 3 times or more, judge that there is a fault in the fuel system.
Time Needed for Diagnosis: 10 s × 3 times
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Secondary Parameters Enable Conditions
Main feedback In operation
Judgment Value
Malfunction Criteria Threshold Value
faf × (1+flaf) < Value from Map
faf = Main feedback compensation coefficient
flaf = main feedback learning compensation coefficient
Map
Warm-up increase compen-
sation coefficient
0.00 0.10 0.20 0.30 0.33 0.50 0.60
Threshold Value 0.650 0.550 0.458 0.383 0.360 0.360 0.360
15WRX_STI_US_EN.book 86 ペー   
GD(w/o STI)-87
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BS:DTC P0191 FUEL RAIL PRESSURE SENSOR "A" CIRCUIT RANGE/PER-
FORMANCE
1. OUTLINE OF DIAGNOSIS
Detect the signal stuck of the fuel pressure sensor.
Judge as NG when the voltage change amount per unit time of the fuel pressure sensor does not exceed the
threshold value.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis continuously after starting the engine.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 10 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Engine speed 475 rpm
Fuel cut Not performed
Judgment Value
Malfunction Criteria Threshold Value
Change amount per unit time of fuel pressure sensor voltage 3.8 V/s
15WRX_STI_US_EN.book 87 ペー   
GD(w/o STI)-88
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BT:DTC P0192 FUEL RAIL PRESSURE SENSOR CIRCUIT LOW
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of the fuel pressure sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2500 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Output voltage (B) Absolute pressure
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage < 0.23 V
EN-10448
(B)
(A)
15WRX_STI_US_EN.book 88 ペー   
GD(w/o STI)-89
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BU:DTC P0193 FUEL RAIL PRESSURE SENSOR CIRCUIT HIGH
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of the fuel pressure sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2500 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Output voltage (B) Absolute pressure
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage > 3.25 V
EN-10448
(B)
(A)
15WRX_STI_US_EN.book 89 ペー   
GD(w/o STI)-90
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BV:DTC P0196 ENGINE OIL TEMPERATURE SENSOR CIRCUIT RANGE/PER-
FORMANCE
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of the engine oil temperature sensor output properties. Using the following two diag-
noses, judge as NG when either is NG.
Diagnosis 1 (correlation diagnosis): After the engine starts after the specified period of soaking time has
elapsed, diagnose by correlation between engine oil temperature sensor value, engine coolant temperature
sensor value and intake air temperature sensor value. Judge as NG when the differences are both above the
specified value by comparing between engine oil temperature and engine coolant temperature, engine oil
temperature and intake air temperature.
Diagnosis 2 (function diagnosis): Judge as NG when engine oil temperature does not rise to the spec-
ified value regardless of an engine running condition that clears certain conditions.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Diagnosis 1: Perform the diagnosis only once after the engine starts after a certain period of soaking time.
Diagnosis 2: Perform the diagnosis only once after starting the engine from cold condition.
(A) Resistance value (kΩ) (B) Temperature °C (°F)
(1) Connector (2) Thermistor element
Diagnosis 1
Secondary Parameters Enable Conditions
Soaking time 21600 s
Block heater judgment Completed
Block heater operation Not in operation
Diagnosis 2
Secondary Parameters Enable Conditions
Engine oil temperature at engine starting < 50°C (122°F)
Engine speed > 475 rpm
Idling ratio 50%
EN-02917
(A)
(2)
(1)
(B)
15WRX_STI_US_EN.book 90 ペー   
GD(w/o STI)-91
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
Judge as NG when Diagnosis 1 or Diagnosis 2 becomes NG.
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Diagnosis 1
Time Needed for Diagnosis: Less than 1 second
Diagnosis 2
Time Needed for Diagnosis: Value of Map 2
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
|Engine oil temperature at engine start – Engine coolant temperature at engine start| > 10°C (18°F)
|Engine oil temperature at engine start – Intake air temperature 30 sec. after engine start| > Value of Map 1
Map 1
Ambient air temperature
°C (°F)
–30
(–22)
30
(86)
45
(113)
60
(140)
|Engine oil temperature at engine start – Intake air tempera-
ture 30 sec. after engine start|
°C (°F)
10
(18)
10
(18)
22
(39.6)
22
(39.6)
Judgment Value
Malfunction Criteria Threshold Value
Engine oil temperature < 50°C (122°F)
Elapsed time after starting the engine Value from Map 2
Map 2
Intake air temperature at engine start
°C (°F)
–30
(–22)
–20
(–4)
–10
(14)
0
(32)
10
(50)
20
(68)
30
(86)
40
(104)
Elapsed time after starting the engine
s
2,800 2,100 1,400 900 650 500 400 400
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GD(w/o STI)-92
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BW:DTC P0197 ENGINE OIL TEMPERATURE SENSOR LOW
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of the oil temperature sensor.
Judge as NG when outside of the judgment value.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 0.5 seconds
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Resistance value (kΩ) (B) Temperature °C (°F)
(1) Connector (2) Thermistor element
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage < 0.18 V
EN-02917
(A)
(2)
(1)
(B)
15WRX_STI_US_EN.book 92 ペー   
GD(w/o STI)-93
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BX:DTC P0198 ENGINE OIL TEMPERATURE SENSOR HIGH
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of the oil temperature sensor.
Judge as NG when outside of the judgment value.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 0.5 seconds
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Resistance value (kΩ) (B) Temperature °C (°F)
(1) Connector (2) Thermistor element
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage > 4.71 V
EN-02917
(A)
(2)
(1)
(B)
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GD(w/o STI)-94
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BY:DTC P0222 THROTTLE/PEDAL POSITION SENSOR/SWITCH “B” CIRCUIT
LOW
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of throttle position sensor 2.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 100 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Throttle position sensor 1 signal (3) Throttle position sensor (4) Engine control module (ECM)
(2) Throttle position sensor 2 signal
Secondary Parameters Enable Conditions
Battery voltage 6 V
Judgment Value
Malfunction Criteria Threshold Value
Sensor 2 input voltage < 0.44 V
EN-10493
(1)
(2)
(3)
(4)
15WRX_STI_US_EN.book 94 ペー   
GD(w/o STI)-95
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BZ:DTC P0223 THROTTLE/PEDAL POSITION SENSOR/SWITCH “B” CIRCUIT
HIGH
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of throttle position sensor 2.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 100 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Throttle position sensor 1 signal (3) Throttle position sensor (4) Engine control module (ECM)
(2) Throttle position sensor 2 signal
Secondary Parameters Enable Conditions
Battery voltage 6 V
Judgment Value
Malfunction Criteria Threshold Value
Sensor 2 input voltage > 4.82 V
EN-10493
(1)
(2)
(3)
(4)
15WRX_STI_US_EN.book 95 ペー   
GD(w/o STI)-96
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CA:DTC P0230 FUEL PUMP PRIMARY CIRCUIT
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of fuel pump control unit.
Judge as NG when the NG signal is sent through a diagnostic line coming from the fuel pump control unit.
Fuel pump control unit detects the open or short circuit malfunction for each line, and then sends NG signals
if one of them is found NG.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2520 ms
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(1) Engine control module (ECM) (3) Fuel pump (4) Battery
(2) Fuel pump control unit
Secondary Parameters Enable Conditions
Battery voltage 8 V
Fuel level 15%
Elapsed time after starting the engine 180 s
Fuel pump controller control mode ON
Judgment Value
Malfunction Criteria Threshold Value
Fuel pump control unit output diagnosis signal < 1.5 V
EN-01771
E
E
(3)
(4)
(2)
FPC
DI
FP+
FP-
+B
(1)
15WRX_STI_US_EN.book 96 ペー   
GD(w/o STI)-97
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CB:DTC P023F FUEL PUMP SECONDARY CIRCUIT/OPEN
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of high pressure fuel pump circuit function.
Judge as NG when ECM detects any malfunction in the diagnostic items listed below.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Diagnosis for Power Supply Short
Diagnosis for Ground Short
Diagnosis for Open Circuit
Diagnosis for Overcurrent
Diagnosis for Short Circuit
Time Needed for Diagnosis: TDC × 75 times
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Diagnostic item Malfunction Criteria
Power supply short ECM low side terminal voltage of the high pressure fuel pump circuit is high.
Ground short ECM low side terminal voltage of the high pressure fuel pump circuit is low.
Open circuit High pressure fuel pump current is low.
Overcurrent High pressure fuel pump current is high.
Short circuit The time when the high pressure fuel pump current reaches the target current is short.
Secondary Parameters Enable Conditions
Battery voltage 9.4 V
Engine speed > 0 rpm
Elapsed time after fuel pump current shutdown
(Only power supply short diagnosis and ground short diagnosis)
3.15ms
Judgment Value
Malfunction Criteria Threshold Value
Terminal voltage 4.1 V
Judgment Value
Malfunction Criteria Threshold Value
Terminal voltage 0.8 V
Judgment Value
Malfunction Criteria Threshold Value
Fuel pump current 0.5 A
Judgment Value
Malfunction Criteria Threshold Value
Fuel pump current 22 A
Judgment Value
Malfunction Criteria Threshold Value
Time for reaching target current 0.075 ms
15WRX_STI_US_EN.book 97 ペー   
GD(w/o STI)-98
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CC:DTC P0244 TURBO/SUPER CHARGER WASTEGATE SOLENOID “A”
RANGE/PERFORMANCE
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of wastegate control solenoid valve function.
Judge as NG when becoming high wastegate pressure.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
(A) Turbocharger (B) Intake duct
Secondary Parameters Enable Conditions
None
(A)
(B)
EN-10454
15WRX_STI_US_EN.book 98 ペー   
GD(w/o STI)-99
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Judgment Value
Malfunction Criteria Threshold Value
Intake manifold pressure > Value from Map
Map
Barometric pressure (kPa (mmHg, inHg))
64
(480, 18.9)
70.6
(529.5, 20.8)
77.3
(579.8, 22.8)
84
(630.1, 24.8)
90.6
(679.6, 26.8)
93.3
(699.8, 27.6)
96
(720.1, 28.3)
97.3
(729.8, 28.7)
Engine
speed
(rpm)
1600
159.7
(1197.9, 47.2)
159.7
(1197.9, 47.2)
159.7
(1197.9, 47.2)
159.7
(1197.9, 47.2)
159.7
(1197.9, 47.2)
159.7
(1197.9, 47.2)
159.7
(1197.9, 47.2)
159.7
(1197.9, 47.2)
2400
223.7
(1677.9, 66.1)
223.7
(1677.9, 66.1)
223.7
(1677.9, 66.1)
223.7
(1677.9, 66.1)
223.7
(1677.9, 66.1)
223.7
(1677.9, 66.1)
223.7
(1677.9, 66.1)
223.7
(1677.9, 66.1)
3200
219.2
(1644.1, 64.7)
223.3
(1674.9, 65.9)
229.6
(1722.1, 67.8)
233.7
(1752.9, 69)
233.7
(1752.9, 69)
233.7
(1752.9, 69)
233.7
(1752.9, 69)
233.7
(1752.9, 69)
4000
204.3
(1532.4, 60.3)
210.7
(1580.4, 62.2)
220.4
(1653.1, 65.1)
236.4
(1773.2, 69.8)
240.7
(1805.4, 71.1)
240.7
(1805.4, 71.1)
240.7
(1805.4, 71.1)
240.7
(1805.4, 71.1)
4800
190.9
(1431.9, 56.4)
201.9
(1514.4, 59.6)
213.5
(1601.4, 63)
234.7
(1760.4, 69.3)
245.7
(1842.9, 72.6)
245.7
(1842.9, 72.6)
245.7
(1842.9, 72.6)
245.7
(1842.9, 72.6)
5600
155.1
(1163.3, 45.8)
176.5
(1323.9, 52.1)
187.2
(1404.1, 55.3)
208.6
(1564.6, 61.6)
219.3
(1644.9, 64.8)
234.3
(1757.4, 69.2)
240.7
(1805.4, 71.1)
240.7
(1805.4, 71.1)
kPa (mmHg, inHg)
15WRX_STI_US_EN.book 99 ペー   
GD(w/o STI)-100
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CD:DTC P0245 TURBO/SUPER CHARGER WASTEGATE SOLENOID “A” LOW
1. OUTLINE OF DIAGNOSIS
Detect open or short circuit of the wastegate control solenoid valve.
Judge as NG when the terminal output voltage remains Low during outputting the duty signal.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis after starting the engine.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 640 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Turbocharger (B) Intake duct
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Duty ratio of wastegate control 80%
Judgment Value
Malfunction Criteria Threshold Value
Output voltage 2.2 V
(A)
(B)
EN-10454
15WRX_STI_US_EN.book 100 ージ 20  
GD(w/o STI)-101
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CE:DTC P0246 TURBO/SUPER CHARGER WASTEGATE SOLENOID “A” HIGH
1. OUTLINE OF DIAGNOSIS
Detect open or short circuit of the wastegate control solenoid valve.
Judge as NG when overcurrent is detected.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis after starting the engine.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2250 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
CF:DTC P0300 RANDOM/MULTIPLE CYLINDER MISFIRE DETECTED
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0301. <Ref. to GD(w/o STI)-102, DTC P0301 CYLINDER 1 MIS-
FIRE DETECTED, Diagnostic Trouble Code (DTC) Detecting Criteria.>
(A) Turbocharger (B) Intake duct
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Duty ratio of wastegate control 20%
Judgment Value
Malfunction Criteria Threshold Value
Output current 17 A
(A)
(B)
EN-10454
15WRX_STI_US_EN.book 101 ージ 20  
GD(w/o STI)-102
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CG:DTC P0301 CYLINDER 1 MISFIRE DETECTED
1. OUTLINE OF DIAGNOSIS
Detect the presence of misfire occurrence. (Revolution fluctuation method)
Monitoring Misfire which influences exhaust deterioration (1.5 times of FTP) and catalyst damage is made
obligatory by the law. Misfire affecting these two has two patterns below:
Intermittent misfire (The same cylinder misfires in random, or different cylinders misfire in random.): FTP
1.5 times misfire
Every time misfire (The same cylinder misfires every time.): FTP 1.5 times misfire, Catalyst damage mis-
fire
The following detecting methods are adopted for these detection.
1) Intermittent misfire: FTP 1.5 times misfire
180° Interval Difference Method
360° Interval Difference Method (whole range)
720° Interval Difference Method (3,000 rpm or more)
2) Misfire every time: FTP 1.5 times misfire, Catalyst damage misfire
360° Interval Difference Method
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
If conditions are met, it is possible to detect the misfires from idling to high engine speed. However, in case
any engine load or breakage occurs, perform with the engine at idle.
Perform the diagnosis continuously.
Secondary Parameters Enable Conditions
Fuel shut-off function Not in operation
Fuel level 9 L (2.38 US gal, 1.98 Imp gal)
Vehicle dynamic control or AT torque control Not in operation
Second diagnosis of P0441 Not in operation
Engine speed 400 rpm — 6000 rpm
Intake manifold pressure • Normal ignition
19.1 — 47 kPa (143.3 — 352.5 mmHg, 5.6 — 13.9 inHg) (Changing
depending on engine speed and atmosphere pressure)
• Idling ignition
19.3 — 46.2 kPa (144.8 — 346.5 mmHg, 5.7 — 13.6 inHg) (Changing
depending on engine speed and atmosphere pressure)
15WRX_STI_US_EN.book 102 ージ 20  
GD(w/o STI)-103
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
4. DIAGNOSTIC METHOD
When a misfire occurs, the engine speed will decrease and the crankshaft position speed will change. Cal-
culate the interval difference value (diagnostic value) from crankshaft position speed by the following formu-
la, and judge whether a misfire is occurring or not comparing the calculated result with judgment value. Count
the number of misfires, if the misfire ratio is higher during 1000 revs. or 200 revs., judge corresponding cyl-
inders as NG.
As shown in the following figure, pick a cylinder as the standard and name it omg 0. And the former crank-
shaft position speed is named omg 1, the second former crankshaft position speed is named omg 2, the third
is named omg 3, etc.
Diagnostic value calculation
(Calculate from angle speed)
Misfire detection every single ignition
(Compare diagnostic value with judg-
ment value)
NG judgment (Misfire occurrence judgment required
by the law) (Compare number of misfire with judgment
value)
180° Interval Difference Method
360° Interval Difference Method
720° Interval Difference Method
FTP 1.5 times misfire NG judgment
Catalyst damage misfire NG judgment
(A) Ignition order (B) Crankshaft position speed
EN-01774
#3 #2 #4 #1 #3 #2 #4 #1 #3 #2(A)
(B)
omg0omg1omg2omg3omg4omg5omg6 omg7
15WRX_STI_US_EN.book 103 ージ 20  
GD(w/o STI)-104
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
180° Interval Difference Method
360° Interval Difference Method
Diagnostic value domg 180 = (omg 0 – omg 1) – (omg 1 – omg 2)
Judge as a misfire in the following cases.
domg 180 judgment value of positive side
domg 180 judgment value of negative side
(Diagnostic value before 180° CA)
Diagnostic value domg 360 = (omg 1 – omg 0) – (omg 3 – omg 2)
Misfire judgment domg 360 > Judgment value Judge as misfire
Judged as misfire.
Threshold value (positive number)
Threshold value (negative number)
domg180
domg180
EN-02877
Judged as misfire.
Threshold value
domg360
domg360
EN-03273
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GD(w/o STI)-105
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
720° Interval Difference Method
FTP 1.5 times misfire (Misfire occurrence level which influences exhaust gas)
Time Needed for Diagnosis: 1000 engine revs.
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Diagnostic value domg 720 = (omg 0 – omg 1) – (omg 4 – omg 5)
Judge as a misfire in the following cases.
domg 720 judgment value of positive side
domg 720 judgment value of negative side
(Diagnostic value before 180° CA)
Judgment Value (Judge that malfunction occurs when the misfire ratio is high in 1000 engine revs.)
Malfunction Criteria Threshold Value
FTP emission diagnostic value 37 × 100/2000% in 1000 revs.
domg720
EN-10459
domg720
Judgment value at negative side
Judgment value at positive side
15WRX_STI_US_EN.book 105 ージ 20  
GD(w/o STI)-106
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
Catalyst damage misfire (Misfire occurrence level damaging catalyst)
Map
Time Needed for Diagnosis: 200 engine revs.
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
CH:DTC P0302 CYLINDER 2 MISFIRE DETECTED
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0301. <Ref. to GD(w/o STI)-102, DTC P0301 CYLINDER 1 MIS-
FIRE DETECTED, Diagnostic Trouble Code (DTC) Detecting Criteria.>
CI: DTC P0303 CYLINDER 3 MISFIRE DETECTED
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0301. <Ref. to GD(w/o STI)-102, DTC P0301 CYLINDER 1 MIS-
FIRE DETECTED, Diagnostic Trouble Code (DTC) Detecting Criteria.>
CJ:DTC P0304 CYLINDER 4 MISFIRE DETECTED
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0301. <Ref. to GD(w/o STI)-102, DTC P0301 CYLINDER 1 MIS-
FIRE DETECTED, Diagnostic Trouble Code (DTC) Detecting Criteria.>
Judgment Value
Malfunction Criteria Threshold Value
Catalyst damage misfire diagnostic value Value from Map
Charging efficiency (%)
15 30 45 60 75 90 105 120 135 150 165 180
Engine
speed
(rpm)
700 25 25
1000 25 25 25 25 25 25
1500 25 25 25 25 16.75 16.75 16.75
2000 25 25 25 25 16.75 14.25 12.5
2500 25 25 19.75 17 14.25 12.5 11 11
3000 25 25 19.75 17 14.25 12 10.5 10 7.75 6
3500252519.751714.251197.756555
4000 2519.751714.25118.256.255555
4500 2517.514.2512.596.7555555
5000 2516.7512.5118.25655555
5500 251612117.25555555
6000 251511116555555
15WRX_STI_US_EN.book 106 ージ 20  
GD(w/o STI)-107
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CK:DTC P0327 KNOCK SENSOR 1 CIRCUIT LOW (BANK 1 OR SINGLE SEN-
SOR)
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of knock sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 1000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) To knock sensor harness
(1) Case (3) Piezoelectric element (5) Resistance
(2) Weight (4) Nut
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage < 0.22 V
(1)
(2)
(3)
(4)
(5)
(A)
EN-08987
15WRX_STI_US_EN.book 107 ージ 20  
GD(w/o STI)-108
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CL:DTC P0328 KNOCK SENSOR 1 CIRCUIT HIGH (BANK 1 OR SINGLE SEN-
SOR)
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of knock sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 1000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) To knock sensor harness
(1) Case (3) Piezoelectric element (5) Resistance
(2) Weight (4) Nut
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage > 4.73 V
(1)
(2)
(3)
(4)
(5)
(A)
EN-08987
15WRX_STI_US_EN.book 108 ージ 20  
GD(w/o STI)-109
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CM:DTC P0332 KNOCK SENSOR 2 CIRCUIT LOW (BANK 2)
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of knock sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 1000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) To knock sensor harness
(1) Case (3) Piezoelectric element (5) Resistance
(2) Weight (4) Nut
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage < 0.22 V
(1)
(2)
(3)
(4)
(5)
(A)
EN-08987
15WRX_STI_US_EN.book 109 ージ 20  
GD(w/o STI)-110
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CN:DTC P0333 KNOCK SENSOR 2 CIRCUIT HIGH (BANK 2)
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of knock sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 1000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) To knock sensor harness
(1) Case (3) Piezoelectric element (5) Resistance
(2) Weight (4) Nut
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage > 4.73 V
(1)
(2)
(3)
(4)
(5)
(A)
EN-08987
15WRX_STI_US_EN.book 110 ージ 20  
GD(w/o STI)-111
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CO:DTC P0335 CRANKSHAFT POSITION SENSOR “A” CIRCUIT
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of the crankshaft position sensor.
Judge as NG when the crank signal is not input even though the starter was rotated.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
(A) Intake cam signal RH (B) Intake cam signal LH (C) Crankshaft signal
(1) Crankshaft position sensor (2) Crankshaft position sensor plate (3) Crank shaft one revolution
Secondary Parameters Enable Conditions
Battery voltage 8 V
#1 TDC#4 TDC#2 TDC#3 TDC#1 TDC
40 CA 30 CA40 CA 30 CA
40 CA 30 CA40 CA 30 CA40 CA 30 CA
30 CA
30 CA
EN-10455
(A)
(C)
(B)
40 CA 30 CA
40 CA 30 CA10 CA
(1)
(2)
EN-10456
(3)
15WRX_STI_US_EN.book 111 ージ 20  
GD(w/o STI)-112
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 3000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Judgment Value
Malfunction Criteria Threshold Value
Number of crankshaft position sensor signals during cranking = 0
15WRX_STI_US_EN.book 112 ージ 20  
GD(w/o STI)-113
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CP:DTC P0336 CRANKSHAFT POSITION SENSOR “A” CIRCUIT RANGE/PER-
FORMANCE
1. OUTLINE OF DIAGNOSIS
Detect for faults in crankshaft position sensor output properties.
Judge as NG when there is a problem in the number of crankshaft signals for every revolution of crankshaft.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
(A) Intake cam signal RH (B) Intake cam signal LH (C) Crankshaft signal
(1) Crankshaft position sensor (2) Crankshaft position sensor plate (3) Crank shaft one revolution
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
#1 TDC#4 TDC#2 TDC#3 TDC#1 TDC
40 CA 30 CA40 CA 30 CA
40 CA 30 CA40 CA 30 CA40 CA 30 CA
30 CA
30 CA
EN-10455
(A)
(C)
(B)
40 CA 30 CA
40 CA 30 CA10 CA
(1)
(2)
EN-10456
(3)
15WRX_STI_US_EN.book 113 ージ 20  
GD(w/o STI)-114
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
Judge as NG when the following conditions are established.
Diagnosis 1
Diagnosis 2
Time Needed for Diagnosis: 10 engine revs.
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
Amount of crank sensor signal during 0.5 rev of crankshaft < 14
or
20
Judgment Value
Malfunction Criteria Threshold Value
|(Present value of diagnosis 1) – (Previous value of diagnosis 1)| 1
15WRX_STI_US_EN.book 114 ージ 20  
GD(w/o STI)-115
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CQ:DTC P0340 CAMSHAFT POSITION SENSOR “A” CIRCUIT (BANK 1 OR SIN-
GLE SENSOR)
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of the camshaft position sensor.
When there is no camshaft position signal input continuously, judge as NG.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Diagnosis 1: Perform the diagnosis only once.
Diagnosis 2: Always perform the diagnosis continuously.
(A) Intake cam signal RH (B) Intake cam signal LH (C) Crankshaft signal
(D) Camshaft position signal: When
normal, there will be 3 camshaft
position signals for every 2 crank-
shaft revolutions.
Diagnosis 1
Secondary Parameters Enable Conditions
Battery voltage 8 V
Diagnosis 2
Secondary Parameters Enable Conditions
Battery voltage 8 V
Elapsed time after starting the engine 200 ms
#1 TDC#4 TDC#2 TDC#3 TDC#1 TDC
40 CA 30 CA40 CA 30 CA
40 CA 30 CA40 CA 30 CA40 CA 30 CA
30 CA
30 CA
EN-10457
(A)
(B)
40 CA 30 CA
(D)
(C)
40 CA 30 CA10 CA
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GD(w/o STI)-116
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
Diagnosis 1
Judge as NG when no input status of camshaft position sensor signal continues for 3 sec. during cranking.
Time Needed for Diagnosis: 3 seconds
Diagnosis 2
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 6 engine revs.
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Judgment Value
Malfunction Criteria Threshold Value
Number of camshaft position sensor signals during cranking = 0
Judgment Value
Malfunction Criteria Threshold Value
Amount of camshaft sensor signal during 1.5 revs of crankshaft = 0
15WRX_STI_US_EN.book 116 ージ 20  
GD(w/o STI)-117
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CR:DTC P0341 CAMSHAFT POSITION SENSOR "A" CIRCUIT RANGE/PERFOR-
MANCE (BANK 1 OR SINGLE SENSOR)
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of camshaft position sensor property.
Judge as NG when the number of camshaft signals remains abnormal.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
Judge as NG when the condition continues where the number of camshaft position sensor signals are not 3
times during 2 revs of crankshaft.
Time Needed for Diagnosis: Engine two revolutions × 4 times
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Intake cam signal RH (B) Intake cam signal LH (C) Crankshaft signal
(D) Camshaft position signal: When
normal, there will be 3 camshaft
position signals for every 2 crank-
shaft revolutions.
Secondary Parameters Enable Conditions
Battery voltage 8 V
Judgment Value
Malfunction Criteria Threshold Value
Amount of camshaft sensor signal during 2 revs of crankshaft 3 times
#1 TDC#4 TDC#2 TDC#3 TDC#1 TDC
40 CA 30 CA40 CA 30 CA
40 CA 30 CA40 CA 30 CA40 CA 30 CA
30 CA
30 CA
EN-10457
(A)
(B)
40 CA 30 CA
(D)
(C)
40 CA 30 CA10 CA
15WRX_STI_US_EN.book 117 ージ 20  
GD(w/o STI)-118
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CS:DTC P0345 CAMSHAFT POSITION SENSOR “A” CIRCUIT (BANK 2)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0340. <Ref. to GD(w/o STI)-115, DTC P0340 CAMSHAFT POSI-
TION SENSOR “A” CIRCUIT (BANK 1 OR SINGLE SENSOR), Diagnostic Trouble Code (DTC) Detecting
Criteria.>
CT:DTC P0346 CAMSHAFT POSITION SENSOR "A" CIRCUIT RANGE/PERFOR-
MANCE (BANK 2)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0341. <Ref. to GD(w/o STI)-117, DTC P0341 CAMSHAFT POSI-
TION SENSOR "A" CIRCUIT RANGE/PERFORMANCE (BANK 1 OR SINGLE SENSOR), Diagnostic Trou-
ble Code (DTC) Detecting Criteria.>
15WRX_STI_US_EN.book 118 ージ 20  
GD(w/o STI)-119
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CU:DTC P0351 IGNITION COIL A PRIMARY/SECONDARY CIRCUIT
1. OUTLINE OF DIAGNOSIS
Based on the self-diagnostic result of the ignition coil driving IC, judge the ignition coil driving circuit as normal
or abnormal.
The ignition coil driving IC detects “no ignition” status as a malfunction.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 2500 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
CV:DTC P0352 IGNITION COIL B PRIMARY/SECONDARY CIRCUIT
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0351. <Ref. to GD(w/o STI)-119, DTC P0351 IGNITION COIL A
PRIMARY/SECONDARY CIRCUIT, Diagnostic Trouble Code (DTC) Detecting Criteria.>
CW:DTC P0353 IGNITION COIL C PRIMARY/SECONDARY CIRCUIT
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0351. <Ref. to GD(w/o STI)-119, DTC P0351 IGNITION COIL A
PRIMARY/SECONDARY CIRCUIT, Diagnostic Trouble Code (DTC) Detecting Criteria.>
CX:DTC P0354 IGNITION COIL D PRIMARY/SECONDARY CIRCUIT
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0351. <Ref. to GD(w/o STI)-119, DTC P0351 IGNITION COIL A
PRIMARY/SECONDARY CIRCUIT, Diagnostic Trouble Code (DTC) Detecting Criteria.>
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Engine speed 500 rpm
Judgment Value
Malfunction Criteria Threshold Value
Fault signal from ignition drive IC ON
15WRX_STI_US_EN.book 119 ージ 20  
GD(w/o STI)-120
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CY:DTC P0365 CAMSHAFT POSITION SENSOR “B” CIRCUIT (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of the camshaft position sensor.
When there is no camshaft position signal input continuously, judge as NG.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 6 engine revs.
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Exhaust cam signal RH (B) Exhaust cam signal LH (C) Crankshaft signal
(D) Camshaft position signal: When
normal, there will be 2 camshaft
position signals for every 2 crank-
shaft revolutions.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Elapsed time after starting the engine 0.2 s
Judgment Value
Malfunction Criteria Threshold Value
Amount of camshaft sensor signal during 1.5 revs of crankshaft = 0
#1 TDC#4 TDC#2 TDC#3 TDC#1 TDC
EN-10458
(A)
(B)
(D)
55 CA
55 CA
55 CA
55 CA
55 CA
(C)
40 CA 30 CA10 CA
15WRX_STI_US_EN.book 120 ージ 20  
GD(w/o STI)-121
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
CZ:DTC P0366 CAMSHAFT POSITION SENSOR B CIRCUIT RANGE/PERFOR-
MANCE (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of camshaft position sensor property.
Judge as NG when the number of camshaft signals remains abnormal.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
Judge as NG when the condition continues where the number of camshaft position sensor signals are not 2
times during 2 revs of crankshaft.
Time Needed for Diagnosis: Engine two revolutions × 4 times
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(A) Exhaust cam signal RH (B) Exhaust cam signal LH (C) Crankshaft signal
(D) Camshaft position signal: When
normal, there will be 2 camshaft
position signals for every 2 crank-
shaft revolutions.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
Amount of camshaft sensor signal during 2 revs of crankshaft 2 times
#1 TDC#4 TDC#2 TDC#3 TDC#1 TDC
EN-10458
(A)
(B)
(D)
55 CA
55 CA
55 CA
55 CA
55 CA
(C)
40 CA 30 CA10 CA
15WRX_STI_US_EN.book 121 ージ 20  
GD(w/o STI)-122
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DA:DTC P0390 CAMSHAFT POSITION SENSOR “B” CIRCUIT (BANK 2)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0365. <Ref. to GD(w/o STI)-120, DTC P0365 CAMSHAFT POSI-
TION SENSOR “B” CIRCUIT (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>
DB:DTC P0391 CAMSHAFT POSITION SENSOR B CIRCUIT RANGE/PERFOR-
MANCE (BANK 2)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0366. <Ref. to GD(w/o STI)-121, DTC P0366 CAMSHAFT POSI-
TION SENSOR B CIRCUIT RANGE/PERFORMANCE (BANK 1), Diagnostic Trouble Code (DTC) Detecting
Criteria.>
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DC:DTC P0400 EXHAUST GAS RECIRCULATION FLOW
1. OUTLINE OF DIAGNOSIS
Detect EGR system malfunction.
Intake manifold pressure (negative pressure) is constant because the throttle valve is fully closed during de-
celeration fuel cut. At this time, when the EGR control valve is opened/closed, the intake manifold pressure
will change. EGR System OK/NG is judged by the range of this change.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
During deceleration fuel cut from 40 km/h (24.9 MPH) or more, perform diagnosis only once.
Be careful of vehicle speed and engine speed. (Diagnosis will not be completed if the vehicle speed and en-
gine speed conditions become out of specification due to deceleration.)
(1) Engine control module (ECM) (4) Switching circuit (6) Main relay
(2) Computer unit (CPU) (5) Battery voltage (7) EGR control valve
(3) Detecting circuit
Secondary Parameters Enable Conditions
Engine speed 1300 rpm — 5000 rpm
Ambient air temperature 5°C (41°F)
Battery voltage 10.9 V
Atmospheric pressure 75 kPa (563 mmHg, 22.2 inHg)
Vehicle speed 40 km/h (24.9 MPH)
Deceleration fuel cut of 3000 ms or more Experienced
Neutral switch OFF
EN-09573
(1)
(2)
(3)
(4)
(5)
(6)
(7)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
Measure the pressure values when the enable conditions are established, and perform diagnosis by calcu-
lating those results.
1. Label the intake manifold pressure value as PMOF1, which is observed when enable conditions are es-
tablished, and set the EGR target step to 55 steps (nearly full open).
2. Label the intake manifold pressure value as PMON, which is observed after one second has passed since
EGR target step was set to 55 steps (when the enable conditions were established), and set the EGR target
step to 0.
3. Label the intake manifold pressure as PMOF2, which is observed after one second has passed since EGR
target step was set to 0 (after two seconds have passed since the enable conditions were established).
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 2 seconds
Judgment Value
Malfunction Criteria Threshold Value
PMON – (PMOF1 + PMOF2)/2 < 2.48 kPa (18.6 mmHg, 0.7 inHg)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) 3000 ms (B) 1000 ms (C) 1000 ms
(D) 55 steps
EN-05568
ON
OFF
(Open)
(Close)
(Open)
(Close)
PMOF1
PMON
PMOF2
Deceleration fuel cut
Diagnosis enable condition
EGR target step
EGR actual step
DIagnostic mode timer
Start dignosis
(D)
(A) (B) (C)
Intake manifold pressure
(During normal condition)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DD:DTC P0420 CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect the deterioration of the catalyst function.
Though the rear oxygen sensor output changes slowly with a new catalyst, the sensor output with a deteri-
orated catalyst becomes high and the inversion time is shortened.
For this reason, the catalyst diagnosis is carried out by monitoring the rear oxygen sensor output and com-
paring it with the front oxygen (A/F) sensor output.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis only once at a constant 60 km/h (37.3 MPH) or higher.
(A) Normal (B) Deterioration (C) Output waveform from the front
oxygen (A/F) sensor
(D) Output waveform from the rear
oxygen sensor
(1) Front oxygen (A/F) sensor (2) Rear oxygen sensor (3) Catalytic converter
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Atmospheric pressure 75 kPa (563 mmHg, 22.2 inHg)
Estimated catalyst temperature 480°C (896°F)
Main feedback In operation
Sub feedback In operation
Second diagnosis of P0441 Not in operation
Vehicle speed > 40 km/h (24.9 MPH)
Amount of intake air 5 g/s (0.18 oz/s)
and
< 45 g/s (1.59 oz/s)
Rear oxygen output change from 550 mV or less to 550 mV or more Experienced after fuel cut
Estimated temperature of the rear oxygen sensor element 450°C (842°F)
EN-01713
(A)
(B)
(C) (D)
(1)
(2)
(3)
(3)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
After the enable conditions have been established, calculate the front oxygen (A/F) sensor lambda value de-
viation sum value (Σ |(sglmd
n
– sglmd
n–1
)|), and rear oxygen sensor output voltage deviation sum value (Σ
|(ro2sad
n
– ro2sad
n – 1
)|) in every 32 ms × 4 times. If the front oxygen (A/F) sensor lambda value deviation
sum value (Σ |(sglmd
n
– sglmd
n – 1
)|) is the predetermined value or more, calculate the diagnostic value.
If the duration of time while the following conditions are met is within the time indicated, judge as NG.
Time Needed for Diagnosis: 30 — 55 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
Σ |(ro2sad
n
– ro2sad
n – 1
)| / Σ |(sglmd
n
– sglmd
n – 1
)| > 9
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DE:DTC P0441 EVAPORATIVE EMISSION CONT. SYS. INCORRECT PURGE
FLOW
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of purge flow by the change of ELCM pressure sensor output value before/after purge
introduction.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis only once after engine start.
4. DIAGNOSTIC METHOD
First diagnosis
Pressure decreases when the purge is introduced compared with when the purge is not performed. By using
this, judge if the purge is correctly performed. If there is no pressure decrease, go to the second diagnosis.
Judge as NG when the following conditions are established.
Secondary Parameters Enable Conditions
<Common conditions>
Battery voltage 10.9 V
Atmospheric pressure 75 kPa (563 mmHg, 22.2 inHg)
<First diagnosis>
Total time of canister purge operation 120 s
<Second diagnosis>
1st Stage monitor judgment Fail
Vehicle speed 30 km/h (18.6 MPH)
Main feedback In operation
Estimated ambient temperature value –25°C (–13°F)
(1) 75 Pa (0.6 mmHg, 0.02 inHg)
Judgment Value
Malfunction Criteria Threshold Value
ELCM pressure value when purge is not performed – ELCM pressure value
when purge is performed
< 80 Pa (0.6 mmHg, 0.02 inHg)
EN-10463
(1)
Time
Proceed to 2nd stage
PASS
Threshold
On
Off
Normal condition
Diagnostic value
Pressure
Malfunction condition
Purge duty
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
Time Needed for Diagnosis: 8 — 38 seconds
Second diagnosis
Close the ELCM switching valve, and close the fuel tank completely, and perform the forced purging. If pres-
sure change amount is 667 Pa (5 mmHg, 0.2 inHg) or less, judge as malfunction of purge flow.
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 21 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
ELCM pressure value when purge is not performed – ELCM pressure value
when purge is performed
< 667 Pa (5 mmHg, 0.2 inHg)
EN-10464
On
Pressure
Switching valve
On (Close)
Pass
Malfunction
monitoring
Purge duty
Off (Open)
Off
PASS
Threshold
Diagnostic value
Time
FAIL
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DF:DTC P0451 EVAPORATIVE EMISSION SYSTEM PRESSURE SENSOR/
SWITCH RANGE/PERFORMANCE
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of ELCM pressure sensor output properties.
Judge as NG when the ELCM pressure sensor output value is largely different from the intake manifold pres-
sure when the ignition switch is ON.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis once at ignition ON.
(1) ELCM (5) Vacuum pump (9) Fuel tank
(2) Switching valve (6) Drain filter (10) Canister
(3) Reference orifice (0.02 inch ori-
fice)
(7) Purge control solenoid valve
(4) Pressure sensor (8) Intake manifold
Secondary Parameters Enable Conditions
Elapsed time after ignition switch is turned to ON 0.5 s
and
< 60 s
Soaking time 60 s
ELCM vacuum pump Not in operation
ELCM switching valve Open
Purge control Not in operation
EN-08957
M
(10)
(8)
(6)(5)
(2)
(3)
(4)
(1)
(7)
(9)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 0.32 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
|ELCM pressure sensor output value when ignition switch is ON – intake manifold
pressure (absolute pressure) when ignition switch is ON|
> 12.4 kPa (93 mmHg, 3.7 inHg)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DG:DTC P0452 EVAPORATIVE EMISSION SYSTEM PRESSURE SENSOR/
SWITCH LOW
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of the ELCM pressure sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 1000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) ELCM (5) Vacuum pump (9) Fuel tank
(2) Switching valve (6) Drain filter (10) Canister
(3) Reference orifice (0.02 inch ori-
fice)
(7) Purge control solenoid valve
(4) Pressure sensor (8) Intake manifold
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
Output voltage < 0.92 V
EN-08957
M
(10)
(8)
(6)(5)
(2)
(3)
(4)
(1)
(7)
(9)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DH:DTC P0453 EVAPORATIVE EMISSION SYSTEM PRESSURE SENSOR/
SWITCH HIGH
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of the ELCM pressure sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 1000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) ELCM (5) Vacuum pump (9) Fuel tank
(2) Switching valve (6) Drain filter (10) Canister
(3) Reference orifice (0.02 inch ori-
fice)
(7) Purge control solenoid valve
(4) Pressure sensor (8) Intake manifold
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
Output voltage > 4.25 V
EN-08957
M
(10)
(8)
(6)(5)
(2)
(3)
(4)
(1)
(7)
(9)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DI: DTC P0455 EVAPORATIVE EMISSION SYSTEM LEAK DETECTED (LARGE
LEAK)
1. OUTLINE OF DIAGNOSIS
This diagnosis judges whether the ELCM operation is normal or not, and whether the evaporative emission
system has leak and clogging or not.
To purge the canister, after driving, perform the five hours soaking after ignition switch OFF in order to sta-
bilize the evaporative gas status. * After 5, 7 or 9.5 hours passed, ECM is activated by soaking timer, and the
leak check is started.
Judges whether the ELCM operation is normal or not, by measuring the reference pressure status via refer-
ence orifice (0.02 inch orifice). Judge as malfunction if the reference pressure is out of specified range. Then,
judge whether there is a leak or not, by comparing the pressure (leak pressure) when the reference pressure
and the evaporative emission system are in negative pressure condition. Judge as system leak in the evap-
orative emission system if the leak pressure is higher than reference pressure. Judge as clogging of pipe if
the leak pressure becomes lower than the reference pressure within the specified amount of time.
0.02 inch leak and 0.04 inch leak can be distinguished by measuring the leak pressure.
The diagnosis results are stored inside ECM until the engine is started again.
*: When the test conditions are not met in 5 hours, perform diagnosis at elapsed time of 7 hours. When the
test conditions are not met in 7 hours, perform diagnosis at elapsed time of 9.5 hours.
OUTLINE OF DIAGNOSIS
Diagnostic item
ELCM system (ELCM body) Vacuum pump stuck
Switching valve stuck to open
Switching valve stuck to close
Reference orifice flow large
Reference orifice flow small
Leak check Large leak
0.04 inch leak
Fuel cap loose
Fuel cap off
System malfunction
Very small leak
0.02 inch leak
Clogging of pipe
EN-08949
ref
P
5 hours after ignition switch turned off.
ECM
Vacuum Pump
Switching Valve
Pressure Sensor
Leak detection pump stuck
Vent valve stuck open
Pipe clogging
OFF
:
Orifice side
OFF
OFF
ON
:
Evap. side
ON
ON
Very small leak
Large leak
Vent valve stuck close
Reference orifice high flow
Reference orifice low flow
ref
P
leak
P
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
2. COMPONENT DESCRIPTION
ELCM consists of the pressure sensor, the reference orifice (diameter of 0.02 inch), the vacuum pump which
introduces the negative pressure into evaporative emission system, and the switching valve which switches
the passage to introduce the negative pressure.
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis only once when 5, 7 or 9.5 hours has passed after ignition switch is OFF. For more de-
tail, refer to “OUTLINE OF DIAGNOSIS”. <Ref. to GD(w/o STI)-134, OUTLINE OF DIAGNOSIS, DTC P0455
EVAPORATIVE EMISSION SYSTEM LEAK DETECTED (LARGE LEAK), Diagnostic Trouble Code (DTC)
Detecting Criteria.>
(1) ELCM (5) Vacuum pump (9) Fuel tank
(2) Switching valve (6) Drain filter (10) Canister
(3) Reference orifice (0.02 inch ori-
fice)
(7) Purge control solenoid valve
(4) Pressure sensor (8) Intake manifold
Secondary Parameters Enable Conditions
Activation of soaking timer Completed
Battery voltage 10.9 V
Engine coolant temperature 4.4°C (39.9°F)
and
< 45°C (113°F)
Atmospheric pressure 75 kPa (563 mmHg, 22.2 inHg)
Accumulated purge amount during previous driving cycle Value of Map 1
Map 1
Engine coolant temperature
°C (°F)
0 (32) 30 (86) 35 (95) 40 (104) 45 (113)
Accumulated purge amount during previous
driving cycle
g (oz)
3000
(105.81)
3000
(105.81)
8000
(282.16)
13000
(458.51)
18000
(634.86)
EN-08957
M
(10)
(8)
(6)(5)
(2)
(3)
(4)
(1)
(7)
(9)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
Mode Explanation of Mode Diagnosis Period
A Vacuum pump operation confirmation and characteristics
stability
7 s or less & 300 s
B Measurement of reference pressure for setting the target
negative pressure
40 s or less
C Switching valve operation confirmation 12 s or less
D Clogging of pipe diagnosis and leak pressure measure-
ment
900 s or less
E Reference pressure measurement for judgment 40 s or less
EN-08950
Activated by soak timer
OFF
:
Orifice side
OFF
OFF
ON
ON
ON
:
Evap. side
Evap. System
target pressure calculation
ABC D E
Judge the leak is occurred or
not by comparing the pressures.
ECM
Vacuum Pump
Switching Valve
Pressure Sensor
Mode
EN-08956
ENABLE
CONDITION
satisfied
not satisfied
Mode
A
Mode
B
Mode
C
Mode
D
Mode
E
OK OK OK OK OK
NGNGNGNGNG
END
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
Mode A (Vacuum pump operation confirmation and characteristics stability)
Purpose: Detect the vacuum pump operation trouble.
Judge as NG when the following conditions are established.
Judge as OK if the following conditions are not established, and warm up for five minutes to stabilize the vac-
uum pump characteristics.
Mode B (Measurement of reference pressure for setting the target negative pressure)
1. Purpose: Judge the reference pressure stability.
Judge as NG when the following conditions are established.
2. Purpose: Judge whether the reference pressure is within the normal range, and detect the vacuum pump
and orifice malfunctions.
Judge as NG when the following conditions are established.
Mode C (Switching valve operation confirmation)
Purpose: Measure the pressure increase when switching valve is changed from open to close, and detect the
stuck to open/close malfunctions of the switching valve.
Judge as NG when the following conditions are established.
Judgment Value
Malfunction Criteria Threshold Value DTC
Pressure sensor output value > –224 Pa (–1.7 mmHg, –0.1 inHg) P2404
Judgment Value
Malfunction Criteria Threshold Value DTC
|Pressure sensor maximum output value – Pressure sensor mini-
mum output value|
> 493 Pa (3.7 mmHg, 0.1 inHg) P2404
Judgment Value
Malfunction Criteria Threshold Value DTC
Reference pressure for setting the target negative pressure < Value of Map 2
or
> Value of Map 3
P2404
Map 2
Atmospheric pressure
kPa (mmHg, inHg)
70 (525, 20.7) 80 (600, 23.6) 90 (675, 26.6) 100 (750, 29.5)
Reference pressure for setting the
target negative pressure
Pa (mmHg, inHg)
–3972 (–29.8, –1.2) –4079 (–30.6, –1.2) –4186 (–31.4, –1.2) –4292 (–32.2, –1.3)
Map 3
Atmospheric pressure
kPa (mmHg, inHg)
70 (525, 20.7) 80 (600, 23.6) 90 (675, 26.6) 100 (750, 29.5)
Reference pressure for setting the
target negative pressure
Pa (mmHg, inHg)
–942 (–7.1, –0.3) –1048 (–7.9, –0.3) –1155 (–8.7, –0.3) –1262 (–9.5, –0.4)
Judgment Value
Malfunction Criteria Threshold Value DTC
Pressure sensor output value – Reference pressure for setting the
target negative pressure
< 224 Pa (1.7 mmHg, 0.1 inHg) P2404
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
Mode D (Clogging of pipe diagnosis and leak pressure measurement)
1. Clogging of pipe
Purpose: Measure the time required for the evaporative emission system to reach the target negative
pressure by the vacuum pump, and detect the clogging of pipe trouble.
Judge as clogging of pipe malfunction if the evaporative emission system reaches to the target negative
pressure within the specified time.
Judgment Value
Malfunction Criteria Threshold Value DTC
Time required to reach to the target negative pressure 30 s P1451
When any one of the followings is established:
• Reference pressure for setting the target negative pressure –
Pressure sensor output value
> Value of Map 4
• Pressure sensor output value < –5 kPa (–37.298 mmHg, –1.5 inHg)
Map 4
Time of
nega-
tive
pres-
sure
introduc-
tion
ms
0 100000 200000 300000 400000 500000 600000 700000 800000 900000 1000000 1100000 1200000
Refer-
ence
pres-
sure for
setting
the tar-
get neg-
ative
pres-
sure –
Pres-
sure
sensor
output
value
kPa
(mmHg,
inHg)
0.9
(7.058,
0.3)
0.9
(7.058,
0.3)
0.9
(7.058,
0.3)
0.9
(7.058,
0.3)
0.9
(7.058,
0.3)
0.9
(7.058,
0.3)
0.9
(7.058,
0.3)
0.9
(7.058,
0.3)
0.9
(7.058,
0.3)
0.9
(7.058,
0.3)
0.9
(7.058,
0.3)
0.9
(7.058,
0.3)
0.9
(7.058,
0.3)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
2. Leak pressure measurement
Purpose: Measure the pressure (leak pressure) when the evaporative emission system becomes the neg-
ative pressure by the vacuum pump.
Store the pressure as a leak pressure while the following conditions are met.
Mode E (Measurement of reference pressure for judgment)
1. Purpose: Judge the reference pressure stability.
Judge as NG when the following conditions are established.
2. Purpose: Judge whether the reference pressure is within the normal range, and detect the vacuum pump
and orifice malfunctions. Judge the vacuum pump performance stability.
Judge as NG when the following conditions are established.
3. Purpose: Judge the presence of evaporative emission system leak.
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 23 min
At next engine start, confirm whether the enable conditions are satisfied even though refueling has been
done during soaking, and determine the malfunction.
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
DJ:DTC P0456 EVAPORATIVE EMISSION CONTROL SYSTEM LEAK DETECT-
ED (VERY SMALL LEAK)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0455. <Ref. to GD(w/o STI)-134, DTC P0455 EVAPORATIVE
EMISSION SYSTEM LEAK DETECTED (LARGE LEAK), Diagnostic Trouble Code (DTC) Detecting Crite-
ria.>
Judgment Value
Conditions for storing the leak pressure Threshold Value
When any one of the followings is established:
• Reference pressure for setting the target negative pressure – Pressure sensor
output value
Value of Map 4
• Pressure sensor output value < –5 kPa (–37.298 mmHg, –1.5 inHg)
• Time of negative pressure introduction 900000 ms
Judgment Value
Malfunction Criteria Threshold Value DTC
|Pressure sensor maximum output value – Pressure sensor mini-
mum output value|
> 493 Pa (3.7 mmHg, 0.1 inHg) P2404
Judgment Value
Malfunction Criteria Threshold Value DTC
Reference pressure for judgment < Value of Map 2
or
> Value of Map 3
P2404
Judgment Value
Malfunction Criteria Threshold Value DTC
<Large leak (0.04 inch)> P0455
Leak pressure
lleakjdg = (Reference pressure for judgment) × 0.377 – (–45.5)
lleakjdg (Pa)
<Very small leak (0.02 inch)> P0456
Leak pressure < lleakjdg (Pa)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DK:DTC P0458 EVAPORATIVE EMISSION SYSTEM PURGE CONTROL VALVE
CIRCUIT LOW
1. OUTLINE OF DIAGNOSIS
Detect open or short circuit of the purge control solenoid valve.
Judge as NG when the ECM output level differs from the actual terminal level.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis after starting the engine.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2500 ms
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) To canister (B) To intake manifold
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Purge control solenoid valve control duty 80%
Judgment Value
Malfunction Criteria Threshold Value
Output voltage 2.2 V
EN-08988
(A) (B)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DL:DTC P0459 EVAPORATIVE EMISSION SYSTEM PURGE CONTROL VALVE
CIRCUIT HIGH
1. OUTLINE OF DIAGNOSIS
Detect open or short circuit of the purge control solenoid valve.
Judge as NG when the ECM output level differs from the actual terminal level.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis after starting the engine.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2250 ms
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) To canister (B) To intake manifold
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Purge control solenoid valve control duty 20%
Judgment Value
Malfunction Criteria Threshold Value
Output current 5 A
EN-08988
(A) (B)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DM:DTC P0461 FUEL LEVEL SENSOR “A” CIRCUIT RANGE/PERFORMANCE
1. OUTLINE OF DIAGNOSIS
Detect malfunctions of the fuel level sensor output property.
If the fuel level does not vary in a particular driving condition / engine condition where it should, judge as NG.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) Fuel level (B) Resistance
Secondary Parameters Enable Conditions
Elapsed time after engine starting 5 s
Battery voltage 10.9 V
Fuel injection time sum value 2296.4 s
Judgment Value
Malfunction Criteria Threshold Value
Max. value – min. value of fuel level < 3.646%
EN-10515
0
(B)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DN:DTC P0462 FUEL LEVEL SENSOR “A” CIRCUIT LOW
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of fuel level sensor. Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2560 ms
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(1) Engine control module (ECM) (3) Fuel level sensor (5) Combination meter
(2) Fuel sub level sensor (4) Detecting circuit
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Elapsed time after starting the engine 3000 ms
Judgment Value
Malfunction Criteria Threshold Value
Output voltage < 2.21 V
(5)
(4)
(1)
(2) (3)
EN-10516
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DO:DTC P0463 FUEL LEVEL SENSOR “A” CIRCUIT HIGH
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of fuel level sensor. Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 1040 ms
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(1) Engine control module (ECM) (3) Fuel level sensor (5) Combination meter
(2) Fuel sub level sensor (4) Detecting circuit
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Elapsed time after starting the engine 3000 ms
Judgment Value
Malfunction Criteria Threshold Value
Output voltage > 12 V
(5)
(4)
(1)
(2) (3)
EN-10516
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DP:DTC P0500 VEHICLE SPEED SENSOR “A”
1. OUTLINE OF DIAGNOSIS
Judge as NG when outside of the judgment value.
Judge NG when the received data from VDCCM&H/U is abnormal vehicle speed, and the vehicle speed data
is impossible.
2. COMPONENT DESCRIPTION
Vehicle speed signals are taken in to the VDC control module and hydraulic control unit, and normal/errone-
ous data of the ABS wheel speed sensor is received by CAN communication from the VDC control module
and hydraulic control unit.
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously after the enable conditions have been established.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2560 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
Speed of RH wheel received from VDC control module & hydraulic control unit 300 km/h (186.4 MPH)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DQ:DTC P0506 IDLE AIR CONTROL SYSTEM RPM LOWER THAN EXPECTED
1. OUTLINE OF DIAGNOSIS
Detect the malfunction that actual engine speed is not close to target engine speed during idling. Judge as
NG when actual engine speed is not close to target engine speed during idling.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis continuously at idling after warming up engine.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 15 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Secondary Parameters Enable Conditions
Fuel level 9 L (2.38 US gal, 1.98 Imp gal)
Atmospheric pressure 75.06 kPa (563 mmHg, 22.2 inHg)
Battery voltage 10.9 V
Engine coolant temperature 60°C (140°F)
Elapsed time after starting the engine 10.5 s
Accelerator pedal position = 0%
Lambda value (left and right) 0.851
and
< 1.151
Elapsed time after intake manifold pressure changes by 4 kPa (30 mmHg, 1.2 inHg) or
more
> 5.1 s
Vehicle speed 0 km/h (0 MPH)
Elapsed time after switching neutral position switch to ON/OFF > 5.1 s
Cold start diagnosis Not in operation
Judgment Value
Malfunction Criteria Threshold Value
Actual engine speed – Target engine speed < – 100 rpm
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DR:DTC P0507 IDLE AIR CONTROL SYSTEM RPM HIGHER THAN EXPECTED
1. OUTLINE OF DIAGNOSIS
Detect the malfunction that actual engine speed is not close to target engine speed during idling. Judge as
NG when actual engine speed is not close to target engine speed during idling.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis continuously at idling after warming up engine.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 15 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Secondary Parameters Enable Conditions
Fuel level 9 L (2.38 US gal, 1.98 Imp gal)
Atmospheric pressure 75.06 kPa (563 mmHg, 22.2 inHg)
Battery voltage 10.9 V
Engine coolant temperature 60°C (140°F)
Elapsed time after starting the engine 10.5 s
Accelerator pedal position = 0%
Lambda value (left and right) 0.851
and
< 1.151
Elapsed time after intake manifold pressure changes by 4 kPa (30 mmHg, 1.2
inHg) or more
> 5.1 s
Vehicle speed 0 km/h (0 MPH)
Elapsed time after switching neutral position switch to ON/OFF > 5.1 s
Cold start diagnosis Not in operation
Judgment Value
Malfunction Criteria Threshold Value
Actual engine speed – Target engine speed > 200 rpm
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DS:DTC P050A COLD START IDLE AIR CONTROL SYSTEM PERFORMANCE
1. OUTLINE OF DIAGNOSIS
When cold, the abnormality in the control of target engine speed increase is detected. (P050A)
Judge as NG if the idle speed diagnosis is NG.
Idle speed diagnosis
Judge as NG when actual engine speed is not close to target engine speed at cold start.
Detect malfunctions of the catalyst advanced idling retard angle control. (P050B)
Judge as NG when ECM is not controlling the angle properly during catalyst advanced idling retard angle
control.
Final ignition timing diagnosis
Judge as NG when actual retard amount is under the specified value at cold start.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis at cold start.
Secondary Parameters Enable Conditions
<Idle speed diagnosis>
Atmospheric pressure 75 kPa (563 mmHg, 22.2 inHg)
Battery voltage 10.9 V
Vehicle speed 2 km/h (1.3 MPH)
Engine coolant temperature 75°C (167°F)
Intake air amount sum value < Value from Map
Elapsed time after gear position change
(P ←→ D or N ←→ D)
3000 ms
Throttle opening angle < 0.312%
Elapsed time after starting the engine 2000 ms
<Final ignition timing diagnosis>
Atmospheric pressure 75 kPa (563 mmHg, 22.2 inHg)
Battery voltage 10.9 V
Vehicle speed 2 km/h (1.3 MPH)
Engine coolant temperature 75°C (167°F)
Intake air amount sum value < Value from Map
Elapsed time after gear position change
(P ←→ D or N ←→ D)
3000 ms
Throttle opening angle < 0.312%
Target retard amount 10°CA
Map
Engine coolant temperature at engine
starting
°C (°F)
–40
(–40)
–30
(–22)
–20
(–4)
–10
(–14)
0
(32)
10
(50)
20
(68)
30
(86)
Intake air amount sum value
g (oz)
723
(25.5)
723
(25.5)
603
(21.27)
683
(24.09)
710
(25.04)
687
(24.23)
570
(20.1)
607
(21.41)
Engine coolant temperature at engine starting
°C (°F)
40
(104)
50
(122)
60
(140)
70
(158)
75
(167)
Intake air amount sum value
g (oz)
607
(21.41)
607
(21.41)
553
(19.5)
467
(16.47)
467
(16.47)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
4. DIAGNOSTIC METHOD
Idle speed diagnosis
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 7 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Final ignition timing diagnosis
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 7 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
DT:DTC P050B COLD START IGNITION TIMING PERFORMANCE
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P050A. <Ref. to GD(w/o STI)-148, DTC P050A COLD START IDLE
AIR CONTROL SYSTEM PERFORMANCE, Diagnostic Trouble Code (DTC) Detecting Criteria.>
Judgment Value
Malfunction Criteria Threshold Value
Actual engine speed – Target engine speed < – 300 rpm
Judgment Value
Malfunction Criteria Threshold Value
Final ignition timing – ignition timing during CSERS*
*: Ignition timing during CSERS (Cold Start Emission Reduction Strategy) = Base
ignition timing – retard amount
> 12°CA
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DU:DTC P0512 STARTER REQUEST CIRCUIT
1. OUTLINE OF DIAGNOSIS
Detect abnormal continuity in the starter SW.
Judge as ON NG when the starter SW signal remains ON.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as ON
NG.
Time Needed for Diagnosis: 30 seconds
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 8 V
Engine speed > 500 rpm
Judgment Value
Malfunction Criteria Threshold Value
Starter SW1 voltage 6 V
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DV:DTC P0560 SYSTEM VOLTAGE
1. OUTLINE OF DIAGNOSIS
Detect the open/short circuit of back-up power supply circuit.
Judge as NG when the backup power voltage is low.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis continuously after starting the engine.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2560 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Engine speed > 500 rpm
Battery voltage 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
Voltage of back-up power supply < 6 V
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DW:DTC P0604 INTERNAL CONTROL MODULE RANDOM ACCESS MEMORY
(RAM) ERROR
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of microcomputer (RAM).
When there is a problem in the CPU normal RAM, judge as NG.
If it is possible to write data to the whole area of RAM in the initial routine, and is possible to read the same
data, it is judged as OK, and if not, NG.
2. ENABLE CONDITIONS
Diagnosis with the initial routine.
3. GENERAL DRIVING CYCLE
Perform the diagnosis as soon as the ignition switch is turned to ON.
4. DIAGNOSTIC METHOD
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
ECM initialization Executed
Judgment Value
Malfunction Criteria Threshold Value
Write the specified value into the RAM. Different from written value
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DX:DTC P0605 INTERNAL CONTROL MODULE READ ONLY MEMORY (ROM)
ERROR
1. OUTLINE OF DIAGNOSIS
Judge as NG when SUM value of ROM is outside the standard value.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis when the ignition switch is turned from OFF to ON.
4. DIAGNOSTIC METHOD
Judge as NG if the criteria below are met.
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
ECM initialization Executed
Judgment Value
Malfunction Criteria Threshold Value
SUM value of ROM Malfunction
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DY:DTC P0606 CONTROL MODULE PROCESSOR
1. OUTLINE OF DIAGNOSIS
Judge as NG when any one of the followings is established.
(1) When the input amplifier circuit operation of throttle position sensor 1 is abnormal.
(2) When the learning value of backup RAM is incorrect.
(3) When SUM value of backup RAM is outside the standard value.
(4) When the communication between main CPU and sub CPU is abnormal.
(5) If the CPU operation is abnormal
(6) If the CPU operation is abnormal (FPU check).
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
(1) Perform the diagnosis only once.
(2) Always perform the diagnosis continuously.
(3) Perform the diagnosis only once.
(4) Always perform the diagnosis continuously.
(5) Always perform the diagnosis continuously.
(6) Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
Judge as NG if the criteria below are met.
Time Needed for Diagnosis:
(1): Less than 1 second
(2): Less than 1 second
(3): Less than 1 second
(4): Less than 1 second
(5): Less than 1 second
(6): 200 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
(1) ECM initialization Executed
(2) Ignition switch OFF ON
(3) ECM initialization Executed
(4) Battery voltage 6 V
(5) Battery voltage 6 V
(6) Battery voltage 6 V
Judgment Value
Malfunction Criteria Threshold Value
(1) Throttle minimum stop position 2.2 V
(2) The learned value of accelerator pedal position in back-up RAM area 1 The learned value of accelerator pedal posi-
tion in back-up RAM area 2
(3) The sum of back-up RAM at the ECM shut down The sum of back-up RAM at the ECM pow-
ered-on
(4) Communication between main CPU and sub CPU Lost
(5) The calculated data of throttle control by main CPU The calculated data of throttle control by sub
CPU
(6) The calculated data by main CPU The calculated data by FPU
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
DZ:DTC P060A INTERNAL CONTROL MODULE MONITORING PROCESSOR
PERFORMANCE
1. OUTLINE OF DIAGNOSIS
Judge as NG when the monitoring IC operation is abnormal.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
Judge as NG when one of the following conditions is established.
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Communication status between main CPU and sub CPU Malfunction
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EA:DTC P060B INTERNAL CONTROL MODULE A/D PROCESSING PERFOR-
MANCE
1. OUTLINE OF DIAGNOSIS
Judge as NG when the AD converter operation is abnormal.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
Judge as NG when one of the following conditions is established.
Time Needed for Diagnosis: 200 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 6 V
|A/D for control – Last value of A/D for control| 0.5 V
Judgment Value
Malfunction Criteria Threshold Value
Change amount of A/D for control 0.2 V
Change amount of A/D for monitoring 0.2 V
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EB:DTC P0616 STARTER RELAY CIRCUIT LOW
1. OUTLINE OF DIAGNOSIS
Detect abnormal continuity in the starter SW 2.
Judge as OFF NG when the starter SW 2 signal remains OFF.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis only once after starting the engine.
4. DIAGNOSTIC METHOD
Judge as OFF NG when the following conditions are established.
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 8 V
Vehicle speed < 1 km/h (0.6 MPH)
Engine speed Increases from 0 rpm to 500 rpm or more
Starter relay ON
Judgment Value
Malfunction Criteria Threshold Value
Starter SW2 signal of 6 V or more Not detected
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EC:DTC P0617 STARTER RELAY CIRCUIT HIGH
1. OUTLINE OF DIAGNOSIS
Detect abnormal continuity in the starter SW 2.
Judge as ON NG when the starter SW 2 signal remains ON.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis continuously after starting the engine.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 30 seconds
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 8 V
Engine speed > 500 rpm
Starter relay OFF
Judgment Value
Malfunction Criteria Threshold Value
Starter SW2 signal 6 V
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
ED:DTC P062D FUEL INJECTOR DRIVER CIRCUIT PERFORMANCE (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of fuel injector circuit function.
Judge as NG when ECM with two fuel injectors or more detects any malfunction in the diagnostic items listed
below.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Diagnosis for Overcurrent
Low Current Diagnosis
Time Needed for Diagnosis: TDC × 50 times
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Diagnostic item Malfunction Criteria
Overcurrent Fuel injector current is high.
Low current Fuel injector current is low.
Secondary Parameters Enable Conditions
Battery voltage 9.4 V
Engine speed > 0 rpm
Fuel cut Not performed
Judgment Value
Malfunction Criteria Threshold Value
Fuel injector current 18 A
Judgment Value
Malfunction Criteria Threshold Value
Fuel injector current 8.8 A
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EE:DTC P062F INTERNAL CONTROL MODULE EEPROM ERROR
1. OUTLINE OF DIAGNOSIS
Judge as NG when the EEPROM operation is abnormal.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis during self shut.
4. DIAGNOSTIC METHOD
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Writing result to EEPROM Malfunction
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EF:DTC P0685 ECM/PCM POWER RELAY CONTROL CIRCUIT/OPEN
1. OUTLINE OF DIAGNOSIS
Detect the main relay stuck to ON.
Judge as NG when ECM keeps operating for more than predetermined time although the main relay does not
turn to OFF after ignition switch is turned to OFF.
2. COMPONENT DESCRIPTION
The main relay controls current of coils by receiving instructions from the ignition switch and ELCM to switch
ECM to ON/OFF.
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis only once when the following driving cycle starts after the ignition switch is OFF.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2.5 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Secondary Parameters Enable Conditions
Main relay OFF instruction
Judgment Value
Malfunction Criteria Threshold Value
ECM status In operation
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EG:DTC P0700 TRANSMISSION CONTROL SYSTEM (MIL REQUEST)
1. OUTLINE OF DIAGNOSIS
Judge as NG when there is CAN communication with the TCM and there is a MIL lighting request.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2560 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
MIL lighting request from TCM Yes
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EH:DTC P081A STARTER DISABLE CIRCUIT LOW
1. OUTLINE OF DIAGNOSIS
Detect abnormal continuity in the starter cut relay.
Judge as NG when the starter cut relay output line is open.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis only once when the engine condition is turned from before starting to after starting.
4. DIAGNOSTIC METHOD
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 2500 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 8 V
Vehicle speed < 1 km/h (0.6 MPH)
Starter cut relay OFF
Engine speed Increases from 0 rpm to 500 rpm or more
Judgment Value
Malfunction Criteria Threshold Value
Starter cut relay control signal that exceeds 3.2 V Not detected
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EI: DTC P0851 PARK/NEUTRAL SWITCH INPUT CIRCUIT LOW (AT MODEL)
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of neutral SW.
Judge as NG when the ECM neutral terminal input differs from the reception data from TCM.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis only once after the enable conditions have been established.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 80 ms × 80 time(s)
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Starter relay feedback voltage < 1.5 V
Engine speed 500 rpm
Data received from TCM “P” range/“N” range
Judgment Value
Malfunction Criteria Threshold Value
Neutral position switch voltage 1 V
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EJ:DTC P0851 NEUTRAL SWITCH INPUT CIRCUIT LOW (MT MODEL)
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of neutral SW.
Judge as NG when there is no change in the neutral SW even if the driving shift was applied. (There is neutral
SW ON/OFF inversion from the vehicle speed and engine speed.)
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis only once after the enable conditions have been established.
4. DIAGNOSTIC METHOD
Judge NG when the malfunction criteria below are completed determined times or more after the neutral SW
change.
Time Needed for Diagnosis: 3 times
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Change from driving condition a) to b) = 3 times
a) Engine speed 600 — 900 rpm & Vehicle speed = 0 km/h (0 MPH)
b) Engine speed 1450 — 2250 rpm & Vehicle speed 64 km/h (39.8 MPH)
Judgment Value
Malfunction Criteria Threshold Value
Neutral switch output voltage 1 V
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EK:DTC P0852 PARK/NEUTRAL SWITCH INPUT CIRCUIT HIGH (AT MODEL)
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of neutral SW.
Judge as NG when the ECM neutral terminal input differs from the reception data from TCM.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis only once after the enable conditions have been established.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 80 ms × 80 time(s)
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Starter relay feedback voltage < 1.5 V
Engine speed 500 rpm
Data received from TCM = “P” range/“N” range
Judgment Value
Malfunction Criteria Threshold Value
Neutral position switch voltage 6.6 V
15WRX_STI_US_EN.book 166 ージ 20  
GD(w/o STI)-167
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EL:DTC P0852 NEUTRAL SWITCH INPUT CIRCUIT HIGH (MT MODEL)
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of neutral SW.
Judge as NG when there is no change in the neutral SW even if the driving shift was applied. (There is neutral
SW ON/OFF inversion from the vehicle speed and engine speed.)
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis only once after the enable conditions have been established.
4. DIAGNOSTIC METHOD
Judge NG when the malfunction criteria below are completed determined times or more after the neutral SW
change.
Time Needed for Diagnosis: 3 times
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Change from driving condition a) to b) = 3 times
a) Engine speed 600 — 900 rpm & Vehicle speed = 0 km/h (0 MPH)
b) Engine speed 1450 — 2250 rpm & Vehicle speed 64 km/h (39.8 MPH)
Judgment Value
Malfunction Criteria Threshold Value
Neutral switch output voltage 6.6 V
15WRX_STI_US_EN.book 167 ージ 20  
GD(w/o STI)-168
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EM:DTC P1134 A/F SENSOR MICRO-COMPUTER PROBLEM
1. OUTLINE OF DIAGNOSIS
Judge as NG when the A/F sensor microcomputer operation is abnormal.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 80 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Communication status between CPU and A/F sensor microcomputer Malfunction
15WRX_STI_US_EN.book 168 ージ 20  
GD(w/o STI)-169
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EN:DTC P113A O2 SENSOR CIRCUIT (OPEN) (BANK1 SENSOR2)
1. OUTLINE OF DIAGNOSIS
Detect open circuit of the rear oxygen sensor. Judge as NG when the rear oxygen sensor voltage can be de-
termined as abnormal while observing the way the rear oxygen sensor gets energized.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously after the enable conditions have been established.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 1 second
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) Electromotive force (B) Air fuel ratio (C) Lean
(D) Rich (E) Theoretical air fuel ratio (F) Comparative voltage
Secondary Parameters Enable Conditions
Engine speed 500 rpm
Battery voltage 10.9 V
Continuous time when the rear oxygen sensor heater control duty exceeds 0% 21.8 s
Accumulated duty ratio of energized rear oxygen sensor heater since engine start 54400%
Rear oxygen sensor offset signal 1.7 — 2.3 V
Judgment Value
Malfunction Criteria Threshold Value
Rear oxygen sensor signal < 1.7 V
EN-10447
(E)
(F)
(C) (B) (D)
(A)
15WRX_STI_US_EN.book 169 ージ 20  
GD(w/o STI)-170
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EO:DTC P1160 RETURN SPRING FAILURE
1. OUTLINE OF DIAGNOSIS
Judge as NG when the throttle opening angle is out of specified value with ignition switch OFF.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Perform the diagnosis when the ignition switch is turned from ON to OFF.
4. DIAGNOSTIC METHOD
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Ignition switch OFF
Continuous time when throttle motor control duty is 0% = 7.82 s
Judgment Value
Malfunction Criteria Threshold Value
Throttle opening angle < 13.9%
or
> 20.6%
15WRX_STI_US_EN.book 170 ージ 20  
GD(w/o STI)-171
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EP:DTC P1261 DI INJECTOR CIRCUIT / OPEN - (CYLINDER 1)
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of fuel injector circuit function.
Judge as NG when ECM detects any malfunction in the diagnostic items listed below.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Diagnosis for Power Supply Short
Diagnosis for Ground Short
Diagnosis for Open Circuit
Diagnosis for Overcurrent
Diagnosis for Short Circuit
Time Needed for Diagnosis: TDC × 50 times
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Diagnostic item Malfunction Criteria
Power supply short ECM low side terminal voltage of the fuel injector circuit is high.
Ground short ECM low side terminal voltage of the fuel injector circuit is low.
Open circuit Fuel injector current is low.
Overcurrent Fuel injector current is high.
Short circuit The time when the fuel injector current reaches the target current is short.
Secondary Parameters Enable Conditions
Battery voltage 9.4 V
Engine speed > 0 rpm
Fuel cut Not performed
Judgment Value
Malfunction Criteria Threshold Value
Terminal voltage 4.1 V
Judgment Value
Malfunction Criteria Threshold Value
Terminal voltage 0.8 V
Judgment Value
Malfunction Criteria Threshold Value
Fuel injector current 0.5 A
Judgment Value
Malfunction Criteria Threshold Value
Fuel injector current 22 A
Judgment Value
Malfunction Criteria Threshold Value
Time for reaching target current 0.075 ms
15WRX_STI_US_EN.book 171 ージ 20  
GD(w/o STI)-172
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EQ:DTC P1262 DI INJECTOR CIRCUIT / OPEN - (CYLINDER 2)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P1261. <Ref. to GD(w/o STI)-171, DTC P1261 DI INJECTOR CIR-
CUIT / OPEN - (CYLINDER 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>
ER:DTC P1263 DI INJECTOR CIRCUIT / OPEN - (CYLINDER 3)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P1261. <Ref. to GD(w/o STI)-171, DTC P1261 DI INJECTOR CIR-
CUIT / OPEN - (CYLINDER 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>
ES:DTC P1264 DI INJECTOR CIRCUIT / OPEN - (CYLINDER 4)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P1261. <Ref. to GD(w/o STI)-171, DTC P1261 DI INJECTOR CIR-
CUIT / OPEN - (CYLINDER 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>
15WRX_STI_US_EN.book 172 ージ 20  
GD(w/o STI)-173
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
ET:DTC P1449 EVAPORATIVE EMISSION CONT. SYS. AIR FILTER CLOG
1. OUTLINE OF DIAGNOSIS
Detect the drain filter clogging by the pressure change during purge introduction.
Judge as drain filter clogging malfunction if the pressure in the evaporative emission system piping suddenly
decreases by the purging.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously when purging is performed after 20000 ms have passed since the
engine started.
(1) ELCM (5) Vacuum pump (9) Fuel tank
(2) Switching valve (6) Drain filter (10) Canister
(3) Reference orifice (0.02 inch ori-
fice)
(7) Purge control solenoid valve
(4) Pressure sensor (8) Intake manifold
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Elapsed time after starting the engine 20000 ms
ELCM vacuum pump Not in operation
ELCM switching valve Open
Continuous time of following conditions 18.12 s
Pressure change in 40 ms 666.61 Pa (5 mmHg, 0.2 inHg)
EN-08957
M
(10)
(8)
(6)(5)
(2)
(3)
(4)
(1)
(7)
(9)
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GD(w/o STI)-174
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
Calculate the difference between the ELCM pressure sensor output value as of 5 seconds ago and the cur-
rent one, and if the value is greater than judgment value, detect and judge as filter clogging trouble.
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 6 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
EU:DTC P1451 EVAPORATIVE EMISSION CONT. SYS.
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0455. <Ref. to GD(w/o STI)-134, DTC P0455 EVAPORATIVE
EMISSION SYSTEM LEAK DETECTED (LARGE LEAK), Diagnostic Trouble Code (DTC) Detecting Crite-
ria.>
Judgment Value
Malfunction Criteria Threshold Value
|Pressure sensor output value as of 5 seconds ago – Current pressure sensor
output value|
> 1370 Pa (10.3 mmHg, 0.4 inHg)
Number of above conditions established > 2 times
EN-08951
purge duty
OK
Malfunction
Evap. Pressure
monitoring value
5 seconds
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GD(w/o STI)-175
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EV:DTC P1458 CPC2 SOLENOID VALVE (CIRCUIT LOW)
1. OUTLINE OF DIAGNOSIS
Detect open or short circuit of the purge control solenoid valve 2.
Judge as NG when the ECM output level differs from the actual terminal level.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis after starting the engine.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2500 ms
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) To canister (B) To intake manifold
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Purge control solenoid valve 2 control signal OFF
Judgment Value
Malfunction Criteria Threshold Value
Output voltage 2.2 V
EN-10460
(A) (B)
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GD(w/o STI)-176
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EW:DTC P1459 CPC2 SOLENOID VALVE (CIRCUIT HIGH)
1. OUTLINE OF DIAGNOSIS
Detect open or short circuit of the purge control solenoid valve 2.
Judge as NG when the ECM output level differs from the actual terminal level.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis after starting the engine.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2250 ms
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) To canister (B) To intake manifold
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Purge control solenoid 2 control signal ON
Judgment Value
Malfunction Criteria Threshold Value
Output current 5 A
EN-10460
(A) (B)
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GD(w/o STI)-177
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
EX:DTC P1492 EGR SOLENOID VALVE SIGNAL #1 CIRCUIT MALFUNCTION
(LOW INPUT)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P1498. <Ref. to GD(w/o STI)-178, DTC P1498 EGR SOLENOID
VALVE SIGNAL #4 CIRCUIT MALFUNCTION (LOW INPUT), Diagnostic Trouble Code (DTC) Detecting Cri-
teria.>
EY:DTC P1493 EGR SOLENOID VALVE SIGNAL #1 CIRCUIT MALFUNCTION
(HIGH INPUT)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P1499. <Ref. to GD(w/o STI)-179, DTC P1499 EGR SOLENOID
VALVE SIGNAL #4 CIRCUIT MALFUNCTION (HIGH INPUT), Diagnostic Trouble Code (DTC) Detecting
Criteria.>
EZ:DTC P1494 EGR SOLENOID VALVE SIGNAL #2 CIRCUIT MALFUNCTION
(LOW INPUT)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P1498. <Ref. to GD(w/o STI)-178, DTC P1498 EGR SOLENOID
VALVE SIGNAL #4 CIRCUIT MALFUNCTION (LOW INPUT), Diagnostic Trouble Code (DTC) Detecting Cri-
teria.>
FA:DTC P1495 EGR SOLENOID VALVE SIGNAL #2 CIRCUIT MALFUNCTION
(HIGH INPUT)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P1499. <Ref. to GD(w/o STI)-179, DTC P1499 EGR SOLENOID
VALVE SIGNAL #4 CIRCUIT MALFUNCTION (HIGH INPUT), Diagnostic Trouble Code (DTC) Detecting
Criteria.>
FB:DTC P1496 EGR SOLENOID VALVE SIGNAL #3 CIRCUIT MALFUNCTION
(LOW INPUT)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P1498. <Ref. to GD(w/o STI)-178, DTC P1498 EGR SOLENOID
VALVE SIGNAL #4 CIRCUIT MALFUNCTION (LOW INPUT), Diagnostic Trouble Code (DTC) Detecting Cri-
teria.>
FC:DTC P1497 EGR SOLENOID VALVE SIGNAL #3 CIRCUIT MALFUNCTION
(HIGH INPUT)
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P1499. <Ref. to GD(w/o STI)-179, DTC P1499 EGR SOLENOID
VALVE SIGNAL #4 CIRCUIT MALFUNCTION (HIGH INPUT), Diagnostic Trouble Code (DTC) Detecting
Criteria.>
15WRX_STI_US_EN.book 177 ージ 20  
GD(w/o STI)-178
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FD:DTC P1498 EGR SOLENOID VALVE SIGNAL #4 CIRCUIT MALFUNCTION
(LOW INPUT)
1. OUTLINE OF DIAGNOSIS
Detects open or short circuit of EGR.
Judge as NG when the ECM output level differs from the actual terminal level.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2500 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Engine control module (ECM) (4) Switch circuit (6) Main relay
(2) Computer unit (CPU) (5) Battery voltage (7) EGR control valve
(3) Detecting circuit
Secondary Parameters Enable Conditions
EGR control signal OFF
Battery voltage 10.9 V
Elapsed time after starting the engine 1 s
Judgment Value
Malfunction Criteria Threshold Value
Terminal voltage 2.2 V
EN-09573
(1)
(2)
(3)
(4)
(5)
(6)
(7)
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GD(w/o STI)-179
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FE:DTC P1499 EGR SOLENOID VALVE SIGNAL #4 CIRCUIT MALFUNCTION
(HIGH INPUT)
1. OUTLINE OF DIAGNOSIS
Detects open or short circuit of EGR.
Judge as NG when the ECM output level differs from the actual terminal level.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2250 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Engine control module (ECM) (4) Switch circuit (6) Main relay
(2) Computer unit (CPU) (5) Battery voltage (7) EGR control valve
(3) Detecting circuit
Secondary Parameters Enable Conditions
EGR control signal ON
Battery voltage 10.9 V
Elapsed time after starting the engine 1 s
Judgment Value
Malfunction Criteria Threshold Value
Terminal current 5 A
EN-09573
(1)
(2)
(3)
(4)
(5)
(6)
(7)
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GD(w/o STI)-180
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FF:DTC P1603 ENGINE STALL HISTORY
1. OUTLINE OF DIAGNOSIS
Judge as NG when the engine stops except by operating the ignition switch after starting the engine.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously after the enable conditions have been established.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 60 ms
Malfunction Indicator Light Illumination: Does not illuminate.
Secondary Parameters Enable Conditions
Engine condition After engine starting
Judgment Value
Malfunction Criteria Threshold Value
Engine speed 300 rpm
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GD(w/o STI)-181
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FG:DTC P1604 STARTABILITY MALFUNCTION
1. OUTLINE OF DIAGNOSIS
Judge as NG when the status enters into any one of the followings.
Although starter signal input is present in ECM, the engine does not start (diagnosis 1)
Although starter signal input is present in ECM, starting takes more time than it should (diagnosis 1)
The engine stops immediately after starting except by operating the ignition switch (diagnosis 2)
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously after the enable conditions have been established.
4. DIAGNOSTIC METHOD
Diagnosis 1
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2 — 26 seconds
Diagnosis 2
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Does not illuminate.
Diagnosis 1
Secondary Parameters Enable Conditions
Starter signal ON
Diagnosis 2
Secondary Parameters Enable Conditions
Elapsed time after starting the engine 2 s
Judgment Value
Malfunction Criteria Threshold Value
Engine speed < 500 rpm
Judgment Value
Malfunction Criteria Threshold Value
Engine speed < 300 rpm
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GD(w/o STI)-182
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FH:DTC P1C00 BATTERY MONITOR MODULE "A"
1. OUTLINE OF DIAGNOSIS
Judge as NG when faulty signal of each part is sent from the battery sensor.
2. COMPONENT DESCRIPTION
The battery sensor monitors the data of battery voltage, current, temperature, etc. ECM receives these data
via LIN communication with the battery sensor.
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously after the enable conditions have been established.
5. DIAGNOSTIC METHOD
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Does not illuminate.
Secondary Parameters Enable Conditions
Ignition switch ON
Judgment Value
Malfunction Criteria Threshold Value
Receives «Internal Error» ON
or
Receives «Temperature Sensor Error» ON
or
Receives «Voltage Sensor Error» ON
or
Receives «Current Sensor Error» ON
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GD(w/o STI)-183
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FI: DTC P2004 INTAKE MANIFOLD RUNNER CONTROL STUCK OPEN (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of tumble generator valve motor function.
Judge open fixing malfunction when the opening degree is large even after finishing the tumble generator
valve closing driving.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 3000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Tumble generator valve “close” signal output time 3.2 s
Judgment Value
Malfunction Criteria Threshold Value
Tumble generator valve opening 57 deg
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FJ:DTC P2005 INTAKE MANIFOLD RUNNER CONTROL STUCK OPEN (BANK 2)
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of tumble generator valve motor function.
Judge open fixing malfunction when the opening degree is large even after finishing the tumble generator
valve closing driving.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 3000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Tumble generator valve “close” signal output time 3.2 s
Judgment Value
Malfunction Criteria Threshold Value
Tumble generator valve opening 57 deg
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GD(w/o STI)-185
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FK:DTC P2006 INTAKE MANIFOLD RUNNER CONTROL STUCK CLOSED
(BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of tumble generator valve motor function.
Judge close fixing malfunction when the opening degree is small even after finishing the tumble generator
valve open driving.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 3000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Tumble generator valve “open” signal output time 4.6 s
Judgment Value
Malfunction Criteria Threshold Value
Tumble generator valve opening < 57 deg
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GD(w/o STI)-186
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FL:DTC P2007 INTAKE MANIFOLD RUNNER CONTROL STUCK CLOSED
(BANK 2)
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of tumble generator valve motor function.
Judge close fixing malfunction when the opening degree is small even after finishing the tumble generator
valve open driving.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 3000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Tumble generator valve “open” signal output time 4.6 s
Judgment Value
Malfunction Criteria Threshold Value
Tumble generator valve opening < 57 deg
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FM:DTC P2009 INTAKE MANIFOLD RUNNER CONTROL CIRCUIT LOW (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of tumble generator valve motor.
Judge as NG when the overcurrent signal is sent from IC after tumble generator valve driving IC diagnosis.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 320 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Engine control module (ECM) (2) Tumble generator valve
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Tumble generator valve drive signal Open or Closed
Judgment Value
Malfunction Criteria Threshold Value
Overcurrent signal from tumble generator valve drive IC ON
E
M
(2)
(1)
EN-09574
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GD(w/o STI)-188
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FN:DTC P2012 INTAKE MANIFOLD RUNNER CONTROL CIRCUIT LOW (BANK 2)
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of tumble generator valve motor.
Judge as NG when the overcurrent signal is sent from IC after tumble generator valve driving IC diagnosis.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 320 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Engine control module (ECM) (2) Tumble generator valve
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Tumble generator valve drive signal Open or Closed
Judgment Value
Malfunction Criteria Threshold Value
Overcurrent signal from tumble generator valve drive IC ON
E
M
(2)
(1)
EN-09574
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GD(w/o STI)-189
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FO:DTC P2016 TUMBLE GENERATED VALVE POSITION SENSOR 1 CIRCUIT
LOW
1. OUTLINE OF DIAGNOSIS
Detect open or short circuit of tumble generator valve position sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 520 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Rotor (3) Voltage (V) (4) Tumble generator valve opening
(°)
(2) Return spring
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage < 0.21 V
EN-10494
(3)
(4)
(1) (2)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FP:DTC P2017 TUMBLE GENERATED VALVE POSITION SENSOR 1 CIRCUIT
HIGH
1. OUTLINE OF DIAGNOSIS
Detect open or short circuit of tumble generator valve position sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 520 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Rotor (3) Voltage (V) (4) Tumble generator valve opening
(°)
(2) Return spring
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage > 4.47 V
EN-10494
(3)
(4)
(1) (2)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FQ:DTC P2021 TUMBLE GENERATED VALVE POSITION SENSOR 2 CIRCUIT
LOW
1. OUTLINE OF DIAGNOSIS
Detect open or short circuit of tumble generator valve position sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 520 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Rotor (3) Voltage (V) (4) Tumble generator valve opening
(°)
(2) Return spring
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage < 0.21 V
EN-10494
(3)
(4)
(1) (2)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FR:DTC P2022 TUMBLE GENERATED VALVE POSITION SENSOR 2 CIRCUIT
HIGH
1. OUTLINE OF DIAGNOSIS
Detect open or short circuit of tumble generator valve position sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 520 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Rotor (3) Voltage (V) (4) Tumble generator valve opening
(°)
(2) Return spring
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage > 4.47 V
EN-10494
(3)
(4)
(1) (2)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FS:DTC P2096 POST CATALYST FUEL TRIM SYSTEM TOO LEAN (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of fuel system from the size of the sub feedback learning value.
Control the sub feedback learning and judge as NG when the learning value is in the lean zone.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis continuously during sub feedback operation.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 1 second
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) Electromotive force (B) Air fuel ratio (C) Lean
(D) Rich (E) Theoretical air fuel ratio (F) Comparative voltage
Secondary Parameters Enable Conditions
Sub feedback In operation
Judgment Value
Malfunction Criteria Threshold Value
Sub feedback learning value –0.073
EN-10447
(E)
(F)
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FT:DTC P2097 POST CATALYST FUEL TRIM SYSTEM TOO RICH (BANK 1)
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of fuel system from the size of the sub feedback learning value.
Sub feedback learning is being performed. When the learning value goes to the rich side, judge as NG.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis continuously during sub feedback operation.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 1 second
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) Electromotive force (B) Air fuel ratio (C) Lean
(D) Rich (E) Theoretical air fuel ratio (F) Comparative voltage
Secondary Parameters Enable Conditions
Sub feedback In operation
Judgment Value
Malfunction Criteria Threshold Value
Sub feedback learning value 0.024
EN-10447
(E)
(F)
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FU:DTC P2101 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT RANGE/
PERFORMANCE
1. OUTLINE OF DIAGNOSIS
In the diagnosis with ignition switch ON, judge as NG when the opening angle with the throttle driven to close
direction is out of the specified range.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis when the ignition switch is turned from OFF to ON.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 190 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Engine control module (ECM) (4) Drive circuit (6) Electronic throttle control relay
(2) Detecting circuit (5) Temperature detection circuit (7) Motor
(3) Overcurrent detection circuit
Secondary Parameters Enable Conditions
Battery voltage 6 V
Judgment Value
Malfunction Criteria Threshold Value
Throttle opening angle during throttle minimum stop position learning 36%
EN-01867
(3)(2)
(5)(2)
(4)
(1)
(6)
(7)
12V 12V
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FV:DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW
1. OUTLINE OF DIAGNOSIS
Judge as NG when the electronic throttle control power is not supplied even when ECM sets the electric con-
trol throttle relay to ON, or when the monitored electronic throttle control relay does not switch to OFF even
when ECM sets the electronic throttle control relay to OFF.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
(1) Engine control module (ECM) (3) Drive circuit (5) Motor
(2) Voltage detection circuit (4) Electronic throttle control relay
Secondary Parameters Enable Conditions
<For electronic throttle control power supply>
Battery voltage 6 V
Electronic throttle control relay output ON
<For electronic throttle control relay monitor>
Battery voltage 10.9 V
Electronic throttle control relay output OFF
EN-01868
(2)
(3)
(1)
(4)
(5)
12V 12V
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 510 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Judgment Value
Malfunction Criteria Threshold Value
<For electronic throttle control power supply>
Electronic throttle control power voltage < 6 V
<For electronic throttle control relay monitor>
Electronic throttle control relay monitor voltage 1.5 V
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FW:DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH
1. OUTLINE OF DIAGNOSIS
Judge as NG when the monitored electronic throttle control relay does not switch to ON even when ECM sets
the electric control throttle relay to ON.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 510 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Engine control module (ECM) (3) Drive circuit (5) Motor
(2) Voltage detection circuit (4) Electronic throttle control relay
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Electronic throttle control relay output ON
Judgment Value
Malfunction Criteria Threshold Value
Electronic throttle control relay monitor voltage 6 V
EN-01868
(2)
(3)
(1)
(4)
(5)
12V 12V
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FX:DTC P2109 THROTTLE/PEDAL POSITION SENSOR “A” MINIMUM STOP
PERFORMANCE
1. OUTLINE OF DIAGNOSIS
Judge as NG when full close point learning cannot conducted or abnormal value is detected.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis at full closed point learning.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 200 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Engine control module (ECM) (3) Motor (4) Throttle position sensor
(2) Drive circuit
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Throttle opening angle when the ignition switch is ON – Throttle minimum stop position < 2.6% (sensor 1)
< 2.6% (sensor 2)
EN-01869
(1)
(2)
(3)
(4)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FY:DTC P2119 THROTTLE ACTUATOR CONTROL THROTTLE BODY RANGE/
PERFORMANCE
1. OUTLINE OF DIAGNOSIS
Judge as NG when the throttle is open stuck, or when the difference between actual throttle opening angle
and estimated opening angle is out of range. Judge as NG when any one of the six items for diagnosis is ap-
plied.
Throttle open stuck:
Throttle opening angle is out of range
Intake air amount is out of range
When the difference between actual throttle opening angle and estimated opening angle is out of
range:
All time monitoring
Actual opening angle change amount is small
Actual opening angle change amount is large
Actual opening angle does not change
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
Item Secondary Parameters Enable Conditions
Throttle opening angle is out of range Battery voltage
DTC P0606 CONTROL MODULE PRO-
CESSOR
6 V
Under detection
Intake air amount is out of range
All time monitoring Battery voltage 6 V
Actual opening angle change amount is small Battery voltage
Actual opening angle change amount
6 V
> 0.84%/ms
Actual opening angle change amount is large Battery voltage
Actual opening angle change amount
6 V
> 2.1%/ms
Actual opening angle does not change Battery voltage
Continuous time when actual opening angle
changing amount is 0%/ms
> 6 V
5 s
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
4. DIAGNOSTIC METHOD
Judge as NG if the criteria below are met.
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Judgment Value
Item Malfunction Criteria Threshold Value
Throttle opening angle is out of range Throttle opening angle 17.3%
Intake air amount is out of range Amount of intake air > 19.2 g/s (0.68 oz/s)
All time monitoring Difference between actual throttle opening
angle and estimated opening angle
4.2%
Actual opening angle change amount is small Difference between actual throttle opening
angle and estimated opening angle
2.1%
Actual opening angle change amount is large Difference between actual throttle opening
angle and estimated opening angle
4.2%
Actual opening angle does not change Difference between actual throttle opening
angle and target throttle opening angle
1.68%
Time Needed for Diagnosis:
Item Time
Throttle opening angle is out of range 200 ms
Intake air amount is out of range 200 ms
All time monitoring 2000 ms
Actual opening angle change amount is small 1000 ms
Actual opening angle change amount is large 500 ms
Actual opening angle does not change 1000 ms
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
FZ:DTC P2122 THROTTLE/PEDAL POSITION SENSOR/SWITCH “D” CIRCUIT
LOW INPUT
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of accelerator pedal position sensor 1.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 100 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Engine control module (ECM) (3) Accelerator pedal position sensor
2 signal
(4) Accelerator pedal position sensor
(2) Accelerator pedal position sensor
1 signal
Secondary Parameters Enable Conditions
Battery voltage 6 V
Judgment Value
Malfunction Criteria Threshold Value
Sensor 1 output voltage < 0.54 V
EN-01861
(2)
(3)
(4)
(1)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GA:DTC P2123 THROTTLE/PEDAL POSITION SENSOR/SWITCH “D” CIRCUIT
HIGH INPUT
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of accelerator pedal position sensor 1.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 100 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Engine control module (ECM) (3) Accelerator pedal position sensor
2 signal
(4) Accelerator pedal position sensor
(2) Accelerator pedal position sensor
1 signal
Secondary Parameters Enable Conditions
Battery voltage 6 V
Judgment Value
Malfunction Criteria Threshold Value
Sensor 1 output voltage > 4.77 V
EN-01861
(2)
(3)
(4)
(1)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GB:DTC P2127 THROTTLE/PEDAL POSITION SENSOR/SWITCH “E” CIRCUIT
LOW INPUT
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of accelerator pedal position sensor 2.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 100 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Engine control module (ECM) (3) Accelerator pedal position sensor
2 signal
(4) Accelerator pedal position sensor
(2) Accelerator pedal position sensor
1 signal
Secondary Parameters Enable Conditions
Battery voltage 6 V
Judgment Value
Malfunction Criteria Threshold Value
Sensor 2 output voltage < 0.54 V
EN-01861
(2)
(3)
(4)
(1)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GC:DTC P2128 THROTTLE/PEDAL POSITION SENSOR/SWITCH “E” CIRCUIT
HIGH INPUT
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of accelerator pedal position sensor 2.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 100 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Engine control module (ECM) (3) Accelerator pedal position sensor
2 signal
(4) Accelerator pedal position sensor
(2) Accelerator pedal position sensor
1 signal
Secondary Parameters Enable Conditions
Battery voltage 6 V
Judgment Value
Malfunction Criteria Threshold Value
Sensor 2 output voltage > 4.77 V
EN-01861
(2)
(3)
(4)
(1)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GD:DTC P2135 THROTTLE/PEDAL POSITION SENSOR/SWITCH “A”/“B” VOLT-
AGE CORRELATION
1. OUTLINE OF DIAGNOSIS
Judge as NG when the signal level of throttle position sensor 1 is different from the throttle position sensor 2.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 120 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) Throttle position sensor 1 signal (3) Throttle position sensor (4) Engine control module (ECM)
(2) Throttle position sensor 2 signal
Secondary Parameters Enable Conditions
Battery voltage 6 V
Judgment Value
Malfunction Criteria Threshold Value
|Throttle position sensor 1 voltage – (5 V – throttle position sensor 2 voltage)| > 0.79 V
EN-10493
(1)
(2)
(3)
(4)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GE:DTC P2138 THROTTLE/PEDAL POSITION SENSOR/SWITCH “D”/“E” VOLT-
AGE CORRELATION
1. OUTLINE OF DIAGNOSIS
Judge as NG when the signal level of accelerator pedal position sensor 1 is different from the accelerator
pedal position sensor 2.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
(1) Engine control module (ECM) (3) Accelerator pedal position sensor
2 signal
(4) Accelerator pedal position sensor
(2) Accelerator pedal position sensor
1 signal
Secondary Parameters Enable Conditions
Battery voltage 6 V
Judgment Value
Malfunction Criteria Threshold Value
Signal difference between two sensors Within NG range of Details of Judgment value
EN-01861
(2)
(3)
(4)
(1)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
Details of Judgment Value
Time Needed for Diagnosis: 140 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(X1) 1.82% (X2) 3.64% (X3) 6.06%
(X4) 12.12%
(Y1) 4.44% (Y2) 4.84% (Y3) 5.04%
(Y4) 7.44% (Y5) 9.44%
EN-10790
(Y2)
(X4)(X3)(X2)(X1)
0
(Y1)
(Y3)
(Y4)
(Y5)
0
Accelerator pedal position sensor 2 opening angle (%)
Sensor output difference (%)
(OK area)
(NG area)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GF:DTC P2146 FUEL INJECTOR POWER SUPPLY A OPEN CIRCUIT
1. OUTLINE OF DIAGNOSIS
Detect the open/short circuit of injector power supply circuit and injector booster circuit.
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
4. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Diagnosis 1
Diagnosis 2
Time Needed for Diagnosis:
Diagnosis 1: 1000 ms
Diagnosis 2: 280 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Injector power supply voltage (diagnosis 2 only) 6 — 17.2 V
Judgment Value
Malfunction Criteria Threshold Value
Injector power supply voltage < 6 V
or
> 17.2 V
Judgment Value
Malfunction Criteria Threshold Value
Injector booster power supply voltage < 5.98 V
or
> 70.72 V
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GG:DTC P2158 VEHICLE SPEED SENSOR "B"
1. OUTLINE OF DIAGNOSIS
Judge as NG when outside of the judgment value.
Judge NG when the received data from VDCCM&H/U is abnormal vehicle speed, and the vehicle speed data
is impossible.
2. COMPONENT DESCRIPTION
Vehicle speed signals are taken in to the VDC control module and hydraulic control unit, and normal/errone-
ous data of the ABS wheel speed sensor is received by CAN communication from the VDC control module
and hydraulic control unit.
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously after the enable conditions have been established.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2560 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
Speed of LH wheel received from VDC control module & hydraulic control unit 300 km/h (186.4 MPH)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GH:DTC P2195 O2 SENSOR SIGNAL BIASED/STUCK LEAN (BANK 1 SENSOR 1)
1. OUTLINE OF DIAGNOSIS
Detect that λ value remains low.
Judge as NG when lambda value is determined as abnormal in accordance with driving conditions such as
intake air amount, sub feedback control, and front oxygen (A/F) sensor λ value and rear oxygen sensor volt-
age value.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis continuously when the conditions are established.
λ value = Actual air fuel ratio/Theoretical air fuel ratio
λ > 1: Lean
λ < 1: Rich
(A) Electromotive force (B) Air fuel ratio (C) Rich
(D) Lean
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Main feedback In operation
Amount of intake air 6 g/s (0.21 oz/s)
Estimated temperature of the rear oxygen sensor element 450°C (842°F)
EN-10446
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 10000 ms
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
λ value < 0.85
Rear oxygen sensor voltage value 150 mV
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GI: DTC P2196 O2 SENSOR SIGNAL BIASED/STUCK RICH (BANK 1 SENSOR 1)
1. OUTLINE OF DIAGNOSIS
Detect that λ value remains high.
Judge as NG when lambda value is determined as abnormal in accordance with driving conditions such as
intake air amount, sub feedback control, and front oxygen (A/F) sensor λ value and rear oxygen sensor volt-
age value.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis continuously when the conditions are established.
λ value = Actual air fuel ratio/Theoretical air fuel ratio
λ > 1: Lean
λ < 1: Rich
(A) Electromotive force (B) Air fuel ratio (C) Rich
(D) Lean
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Main feedback In operation
Amount of intake air 6 g/s (0.21 oz/s)
Estimated temperature of the rear oxygen sensor element 450°C (842°F)
EN-10446
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 10000 ms
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
λ value > 1.15
Rear oxygen sensor voltage value 550 mV
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GJ:DTC P219A BANK 1 AIR-FUEL RATIO IMBALANCE
1. OUTLINE OF DIAGNOSIS
This diagnostic monitor performs a functional check of the fuel system to determine an air-fuel ratio cylinder
imbalance.
This diagnosis is composed of two monitors.
The outline of “monitor A1” is as follows. When an air-fuel ratio cylinder imbalance occurs, the primary oxy-
gen sensor output signal will oscillate with increased amplitude. This monitor utilizes this behavior to make
a diagnosis. The monitor integrates the difference between the amplification value and the mean value of the
first oxygen sensor output signal and compares it to a threshold to make a judgment.
The outline of “monitor B1” is as follows. Similarly, when an imbalance occurs, the engine speed also fluctu-
ates with increased amplitude. This monitor utilizes this behavior to make a diagnosis. For reference, it
should be noted that this imbalance monitor method is actually similar to the current misfire diagnostic mon-
itor, and the parameter “domg360” (units: degrees CA) is shared between the imbalance and misfire moni-
tors. The imbalance monitor is performed during idle condition when the engine is warm. The monitor
integrates the count of “domg360” which exceeds a threshold in 1000 revolution.
When both the “monitor A1” value and the “monitor B1” value exceed a predetermined threshold, this monitor
determines a malfunction and stores a fault code.
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GD(w/o STI)-216
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
Monitor A1
When there is an air-fuel ratio cylinder imbalance malfunction, the primary oxygen sensor output fluctuates
widely compared with a normal sensor, as shown by the chain line in Figure 1 below. This monitor makes a
diagnosis based on this phenomenon. Each primary oxygen sensor signal (PS) and mean value of the pri-
mary oxygen sensor signal (MS) is calculated from the primary oxygen sensor signal. The absolute values
of (PS – MS) are sampled every 4 ms as shown in the figure. Diagnostic value 1 (DV1) is obtained by inte-
grating the absolute value of (PS – MS) for 2500 times. A malfunction is determined when DV1 exceeds the
threshold. The judgment values are determined experimentally.
Figure 1. Compare malfunctioned primary oxygen sensor output with a normal sensor
EN-09840
1cycle (720deg)
PS: Primary oxygen sensor signal
MS: Mean value of the primary
oxygen sensor output signal
Time
PS
Crank angle (degree)
Sampling period
(4ms)
PS
MS
MS
Malfunction criteria : DV1 > Threshold
PS0
PS1
MS0
MS1
Diagnostic value 1 (DV1) = [n=2500]
n-1
k=0
kk
|MS-PS|
MS
k
= (PS
k
– MS
k-1
) x 1/4 + MS
k-1
Malfunction
Normal
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
Monitor B1
Method used: Difference method of 360 degrees CA
Monitor value: domg360 = (omg 1 – omg 0) – (omg 3 – omg 2) = angular speed
Each crankshaft angular speed is defined as Figure 2 below.
Figure 2. Description of domg360 output
This method uses the fact that the domg360 of lean conditioned cylinder caused by imbalance malfunction
indicates big value, as shown by the chain line in Figure 3 below.
The number of times for domg360 to exceed the judgment value in 1000 revolutions (500 cycles) is calculat-
ed as diagnostic value 2 (DV2). A malfunction is determined when DV2 exceeds the threshold.
Figure 3. Compare malfunctioned domg360 output with a normal output
EN-09841
Cyl #1Firing order
omg X = Crankshaft angular speed
X = Sampling timing
For example omg0 = Crankshaft angular speed at the current sampling timing
5 lgnition events before 1 lgnition events before
Current lgnition
lgnition events
Crankshaft
angular
speed
Description
Cyl #3 Cyl #2 Cyl #4 Cyl #1 Cyl #3
omg5 omg4 omg3 omg2 omg1 omg0
Cyl #2
Malfunction criteria : DV2 > Threshold
Diagnostic value 2 (DV2) : The number of times for domg360 to exceed the judgment value.
Malfunction
Diagnostic value2
Normal
domg360
1cycle 1cycle
Cyl #4
Cyl #3
Cyl #1
Cyl #2
Judgement value
EN-09842
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
2. ENABLE CONDITIONS
3. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
Monitor A1: Primary oxygen sensor fluctuation
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Atmospheric pressure 75 kPa (563 mmHg, 22.2 inHg)
Fuel system status (Primary oxygen sensor) Closed loop
Engine speed > 1500 rpm
and
< 4000 rpm
Charging efficiency 80%
Monitor B1: Crankshaft speed fluctuation
Secondary Parameters Enable Conditions
Misfire diagnosis monitor Active
Accelerator pedal position = 0%
Vehicle speed 1.93 km/h (1.2 MPH)
Engine speed > 475 rpm
and
< 900 rpm
Charging efficiency > 0%
and
< 45%
15WRX_STI_US_EN.book 218 ージ 20  
GD(w/o STI)-219
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
4. DIAGNOSTIC METHOD
Judge as NG when Monitor A1 and Monitor B1 are both NG, and when either is OK, judge as OK.
Monitor A1
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 10 seconds
Monitor B1
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 750 engine revs.
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
Diagnostic value 1 (DV1) > Threshold value 1 (TV1)
EN-09888
Threshold value 1 (TV1):
[n=2500]
n-1
k=0
k
Map
Map
Charging efficiency (%)
80 90 100 110 120
Engine
speed
(rpm)
1500 0.006 0.007 0.010 0.006 0.006
2000 0.005 0.008 0.012 0.017 0.018
2500 0.007 0.011 0.018 0.029 0.030
3000 0.011 0.014 0.017 0.029 0.030
3500 0.011 0.016 0.018 0.029 0.030
4000 0.020 0.027 0.024 0.029 0.030
Judgment Value
Malfunction Criteria Threshold Value
Diagnostic Value2 (DV2) > 30 count
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GK:DTC P2227 BAROMETRIC PRESSURE CIRCUIT RANGE/PERFORMANCE
1. OUTLINE OF DIAGNOSIS
Detect the malfunction of barometric pressure sensor output property.
Judge as NG when the barometric pressure sensor output is largely different from the intake manifold pres-
sure at engine start.
2. COMPONENT DESCRIPTION
The barometric pressure sensor is built into the ECM.
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis once at ignition switch ON.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 3.2 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Secondary Parameters Enable Conditions
Soaking time 60 s
Elapsed time after ignition switch is turned to ON < 60 s
Judgment Value
Malfunction Criteria Threshold Value
|Barometric pressure – Intake manifold pressure at engine start| 12.73 kPa (95.5 mmHg, 3.8 inHg)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GL:DTC P2228 BAROMETRIC PRESSURE CIRCUIT LOW
1. OUTLINE OF DIAGNOSIS
Detect the open/short circuit of the barometric pressure sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
The barometric pressure sensor is built into the ECM.
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 520 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage < 1.76 V
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GM:DTC P2229 BAROMETRIC PRESSURE CIRCUIT HIGH
1. OUTLINE OF DIAGNOSIS
Detect the open/short circuit of the barometric pressure sensor.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
The barometric pressure sensor is built into the ECM.
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 520 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
None
Judgment Value
Malfunction Criteria Threshold Value
Output voltage > 4.6 V
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GN:DTC P2270 O2 SENSOR SIGNAL BIASED/STUCK LEAN (BANK 1 SENSOR 2)
1. OUTLINE OF DIAGNOSIS
Detect the stuck of rear oxygen sensor voltage in lean state.
When rear oxygen sensor voltage remains below the threshold value for predetermined time, diagnosis in-
terrupts target air fuel ratio for control and raises output voltage.
Judge as NG detecting the stuck in lean state when rear oxygen sensor voltage remains below the threshold
value even after the interrupt control.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis only once after the enable conditions have been established.
(A) Electromotive force (B) Air fuel ratio (C) Lean
(D) Rich (E) Theoretical air fuel ratio (F) Comparative voltage
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Sub feedback In operation
Amount of intake air 10 g/s (0.35 oz/s)
Estimated temperature of the rear oxygen sensor element 450°C (842°F)
Enable conditions at interrupt control are as follows
Air fuel ratio reduced from target air fuel ratio = Value of Map
Continuous time when rear oxygen sensor output voltage is less than 0.55 V 10 s
Map
Output voltage of rear oxygen sensor
V
0.00 0.10 0.15 0.30 0.40 0.50 0.60
Air fuel ratio reduced from target air fuel ratio
%
151554444
EN-10447
(E)
(F)
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 20 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
Output voltage of rear oxygen sensor < 0.55 V
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GO:DTC P2271 O2 SENSOR SIGNAL BIASED/STUCK RICH (BANK 1 SENSOR 2)
1. OUTLINE OF DIAGNOSIS
Detect the stuck of rear oxygen sensor voltage in rich state.
Detect the stuck in rich state and judge as NG if rear oxygen sensor voltage remains above the threshold val-
ue for predetermined time.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis only once after the enable conditions have been established.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 0.5 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) Electromotive force (B) Air fuel ratio (C) Lean
(D) Rich (E) Theoretical air fuel ratio (F) Comparative voltage
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Deceleration fuel cut of 5000 ms or more Experienced
Estimated temperature of the rear oxygen sensor element 450°C (842°F)
Judgment Value
Malfunction Criteria Threshold Value
Output voltage of rear oxygen sensor > 0.15 V
EN-10447
(E)
(F)
(C) (B) (D)
(A)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GP:DTC P2401 EVAPORATIVE EMISSION SYSTEM LEAK DETECTION PUMP
CONTROL CIRCUIT LOW
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of the ELCM vacuum pump.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis only once after the enable conditions have been established.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2500 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) ELCM (5) Vacuum pump (9) Fuel tank
(2) Switching valve (6) Drain filter (10) Canister
(3) Reference orifice (0.02 inch ori-
fice)
(7) Purge control solenoid valve
(4) Pressure sensor (8) Intake manifold
Secondary Parameters Enable Conditions
Battery voltage 10.9
ELCM vacuum pump drive signal OFF
Judgment Value
Malfunction Criteria Threshold Value
Output voltage 2.2 V
EN-08957
M
(10)
(8)
(6)(5)
(2)
(3)
(4)
(1)
(7)
(9)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GQ:DTC P2402 EVAPORATIVE EMISSION SYSTEM LEAK DETECTION PUMP
CONTROL CIRCUIT HIGH
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of the ELCM vacuum pump.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis only once after the enable conditions have been established.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2250 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) ELCM (5) Vacuum pump (9) Fuel tank
(2) Switching valve (6) Drain filter (10) Canister
(3) Reference orifice (0.02 inch ori-
fice)
(7) Purge control solenoid valve
(4) Pressure sensor (8) Intake manifold
Secondary Parameters Enable Conditions
Battery voltage 10.9
ELCM vacuum pump drive signal ON
Judgment Value
Malfunction Criteria Threshold Value
Output current 5 A
EN-08957
M
(10)
(8)
(6)(5)
(2)
(3)
(4)
(1)
(7)
(9)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GR:DTC P2404 EVAPORATIVE EMISSION SYSTEM LEAK DETECTION PUMP
SENSE CIRCUIT RANGE/PERFORMANCE
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC P0455. <Ref. to GD(w/o STI)-134, DTC P0455 EVAPORATIVE
EMISSION SYSTEM LEAK DETECTED (LARGE LEAK), Diagnostic Trouble Code (DTC) Detecting Crite-
ria.>
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GS:DTC P2419 EVAPORATIVE EMISSION SYSTEM SWITCHING VALVE CON-
TROL CIRCUIT LOW
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of the ELCM switching valve.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis continuously after the enable conditions have been established.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2500 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) ELCM (5) Vacuum pump (9) Fuel tank
(2) Switching valve (6) Drain filter (10) Canister
(3) Reference orifice (0.02 inch ori-
fice)
(7) Purge control solenoid valve
(4) Pressure sensor (8) Intake manifold
Secondary Parameters Enable Conditions
Battery voltage 10.9
ELCM switching valve drive signal OFF
Judgment Value
Malfunction Criteria Threshold Value
Output voltage 2.2 V
EN-08957
M
(10)
(8)
(6)(5)
(2)
(3)
(4)
(1)
(7)
(9)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GT:DTC P2420 EVAPORATIVE EMISSION SYSTEM SWITCHING VALVE CON-
TROL CIRCUIT HIGH
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of the ELCM switching valve.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Perform the diagnosis continuously after the enable conditions have been established.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2250 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
(1) ELCM (5) Vacuum pump (9) Fuel tank
(2) Switching valve (6) Drain filter (10) Canister
(3) Reference orifice (0.02 inch ori-
fice)
(7) Purge control solenoid valve
(4) Pressure sensor (8) Intake manifold
Secondary Parameters Enable Conditions
Battery voltage 10.9
ELCM switching valve drive signal ON
Judgment Value
Malfunction Criteria Threshold Value
Output current 5 A
EN-08957
M
(10)
(8)
(6)(5)
(2)
(3)
(4)
(1)
(7)
(9)
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GU:DTC P2530 IGNITION SWITCH RUN POSITION CIRCUIT
1. OUTLINE OF DIAGNOSIS
Detect instantaneous open in ignition switch input circuit to ECM.
Judge as NG if out of specification.
2. COMPONENT DESCRIPTION
ECM monitors the voltage of the ignition switch input circuit. Judge as ignition switch ON when the voltage
is the specified value or more.
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously after the enable conditions have been established.
5. DIAGNOSTIC METHOD
Judge as NG when the following conditions are established within the predetermined time.
Time Needed for Diagnosis: 5 seconds
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Engine speed 475 rpm
Judgment Value
Malfunction Criteria Threshold Value
Number of instantaneous opens in ignition switch input circuit 5 times
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GV:DTC P2610 ECM/PCM INTERNAL ENGINE OFF TIMER PERFORMANCE
1. OUTLINE OF DIAGNOSIS
Confirm the engine off timer accuracy by comparing engine off timer and power supply IC timer after ignition
switch is turned to OFF.
This diagnosis consists of the following six cases. Judge as NG when in any one of the following cases, ab-
normality is detected.
Case number Diagnosis function Time Needed for Diagnosis:
Case #1
Diagnose the difference between wake-up request
time and power supply IC timer.
Less than 1 second
Case #2
Diagnose the time in power supply IC timer before
wake up.
Less than 1 second
Case #3
Diagnose the communication error between main
CPU and sub CPU.
2 s
Case #4
Diagnose the communication error between main
CPU and power supply IC.
2 s
Case #5
Diagnose the operation status abnormality in main
CPU and sub CPU.
2 s
Case #6
Diagnose the ignition switch status abnormality in
main CPU and sub CPU.
2 s
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
NOTE:
Normal mode: main relay and ignition switch is ON.
Wake-up mode: In soaking
2. COMPONENT DESCRIPTION
The engine off timer is built into the ECM.
3. ENABLE CONDITIONS
Secondary Parameters Enable Conditions
<Case #1>
Battery voltage 10.9 V
Main CPU Wake-up mode
<Case #2>
Battery voltage 10.9 V
Main CPU Normal mode
Wake-up experience flag OFF
<Case #3, #4, #5 and #6>
Battery voltage 10.9 V
#1, #3
#4, #5
#6
#1, #3
#4, #5
#6
#1, #3
#4, #5
#6
#3, #4
#5, #6
#2
#5, #6
057
EN-10510
Ignition switch
Normal mode
Normal mode
Main CPU
Sub CPU
Power supply IC
Engine OFF timer
Power supply IC timer
Diagnosis timing
Time (h)
Main relay
9.5
Wake-up mode
retry
The ELCM monitor
CanceledCanceled
OFF
ON
ON
OFF
ON
OFF
OFF
ON
ON
retry
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
4. GENERAL DRIVING CYCLE
Case #1: Perform the diagnosis only once when wake-up operates after the ignition switch is OFF.
Case #2: Perform the diagnosis only once when the following driving cycle starts after the ignition switch
is OFF.
Case #3: Perform the diagnosis only once after the enable conditions have been established.
Case #4: Perform the diagnosis only once after the enable conditions have been established.
Case #5: Perform the diagnosis only once after the enable conditions have been established.
Case #6: Perform the diagnosis only once after the enable conditions have been established.
5. DIAGNOSTIC METHOD
<Case #1>
Judge as abnormal in engine off timer or power supply IC timer when the difference between wake-up re-
quest time and power supply IC timer exceeds the threshold value.
When the sub CPU is faulty, wake-up timing is either advancing or retarding compared with normal timing.
Processed in order Step 1 through Step 3.
Step1
PASSFAIL FAIL
0
Step2
Step3
EN-10511
Threshold value
Ignition switch
Main relay
Main CPU
Power supply IC and Sub CPU
Engine OFF timer
Wake-up request time
(normal mode)
Power supply IC timer time
Early Delay
OFF
ON
ON
ON
OFF
OFF
ON
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
<Case #2>
Judge as abnormal in engine off timer when the power supply IC timer exceeds the wake-up request time be-
fore wake up.
When case #1 is not performed, perform case #2.
Judgment Value
Malfunction Criteria Threshold Value
|(Power supply IC timer) – (Wake-up request time)| / Wake-up request time > 0.24
Processed in order Step 1 through Step 3.
Step1
PASS FAIL
OFF
ON
0
ON
ON
OFF
OFF
ON
Step2
Step3
OFF
EN-10512
Ignition switch
Main relay
Main CPU
Power supply IC and Sub CPU
Engine OFF timer
Power supply IC timer time
Wake-up experience flag
Threshold value
FAIL detection
Wake-up
request time
No wake-up
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: Less than 1 second
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
<Case #3>
Diagnose the communication error between main CPU and sub CPU.
Judge as NG when the wake-up time required from main CPU and the wake-up time received from sub CPU
are different.
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 2 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
Judgment Value
Malfunction Criteria Threshold Value
{(Power supply IC timer) – (Wake-up request time)} / Wake-up request time > 0.24
(A) Main CPU demands wake-up time to sub CPU.
(B) Sub CPU sends back wake-up time required by main CPU.
Judgment Value
Malfunction Criteria Threshold Value
Wake-up time required by main CPU Wake-up time sent back by sub CPU
(A)
(B)
ECM
EN-10513
Power supply IC
Power supply IC counter
Main CPU Sub CPU
Sub CPU counterECM counter
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
<Case #4>
Diagnose the communication error between main CPU and power supply IC.
Judge as NG when the signal required by main CPU and the signal received from power supply IC are dif-
ferent.
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 2 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) Main CPU demands signals for measuring the wake-up time to power supply IC.
(B) Main CPU receives signals for measuring the wake-up time from power supply IC.
Judgment Value
Malfunction Criteria Threshold Value
Signal required by main CPU Signal received from power supply IC
(A) (B)
ECM
EN-10514
Power supply IC
Power supply IC counter
Main CPU Sub CPU
Sub CPU counterECM counter
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
<Case #5>
On main CPU and sub CPU, there are two operation status: “normal mode” and “wake-up mode”.
Perform diagnosis for CPU operation status abnormality by detecting the difference in operating status of
main CPU and sub CPU.
Judge as NG when main CPU and sub CPU is different in operating status.
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 2 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
<Case #6>
Perform diagnosis for ignition switch status abnormality by detecting the difference in ignition switch status
(ON or OFF) of main CPU and sub CPU.
(A) Main CPU demands diagnosis for operating status to sub CPU.
(B) Sub CPU sends back the operating status to main CPU.
Judgment Value
Malfunction Criteria Threshold Value
Operating status of main CPU Operating status of sub CPU
(A)
(B)
ECM
EN-10513
Power supply IC
Power supply IC counter
Main CPU Sub CPU
Sub CPU counterECM counter
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Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
Judge as NG when main CPU and sub CPU are different in ignition switch status.
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 2 seconds
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cy-
cles.
(A) Main CPU demands ignition switch status to sub CPU.
(B) Sub CPU sends back ignition switch status to main CPU.
Judgment Value
Malfunction Criteria Threshold Value
Ignition switch status of main CPU Ignition switch status of sub CPU
(A)
(B)
ECM
EN-10513
Power supply IC
Power supply IC counter
Main CPU Sub CPU
Sub CPU counterECM counter
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GD(w/o STI)-240
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GW:DTC U0073 CONTROL MODULE COMMUNICATION BUS OFF
1. OUTLINE OF DIAGNOSIS
Detect malfunction of CAN communication.
Judge as NG when CAN communication failure has occurred.
2. COMPONENT DESCRIPTION
(Common Specifications)
CAN Protocol 2.0 B (Active)
Frame Format: 11 Bit ID Frame (Standard Frame)
Conforms to ISO11898
Communication Speed: 500 kbps
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 436 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
CAN bus condition Bus off
15WRX_STI_US_EN.book 240 ージ 20  
GD(w/o STI)-241
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GX:DTC U0077 LIN COMMUNICATION BUS "ECM/PCM" OFF
1. OUTLINE OF DIAGNOSIS
Detect malfunction of LIN communication.
Judge as NG when the data sent/received via LIN communication is abnormal.
2. COMPONENT DESCRIPTION
LIN communication is used to send/receive data between ECM and battery sensor.
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously after the enable conditions have been established.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 1.5 seconds
Malfunction Indicator Light Illumination: Does not illuminate.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
Data sent/received with control modules connected to LIN Does not change
or
Checksum error
15WRX_STI_US_EN.book 241 ージ 20  
GD(w/o STI)-242
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
GY:DTC U0101 LOST COMMUNICATION WITH TCM
1. OUTLINE OF DIAGNOSIS
Detect malfunction of CAN communication.
Judge as NG when CAN communication failure between TCM, VDC CM and combination meter has oc-
curred.
2. COMPONENT DESCRIPTION
(Common Specifications)
CAN Protocol 2.0 B (Active)
Frame Format: 11 Bit ID Frame (Standard Frame)
Conforms to ISO11898
Communication Speed: 500 kbps
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 500 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
GZ:DTC U0122 LOST COMMUNICATION WITH VEHICLE DYNAMICS CONTROL
MODULE
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC U0101. <Ref. to GD(w/o STI)-242, DTC U0101 LOST COMMUNI-
CATION WITH TCM, Diagnostic Trouble Code (DTC) Detecting Criteria.>
HA:DTC U0155 LOST COMMUNICATION WITH INSTRUMENT PANEL CLUSTER
(IPC) CONTROL MODULE
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC U0101. <Ref. to GD(w/o STI)-242, DTC U0101 LOST COMMUNI-
CATION WITH TCM, Diagnostic Trouble Code (DTC) Detecting Criteria.>
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
ID received from control module connected to CAN None
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GD(w/o STI)-243
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
HB:DTC U0402 INVALID DATA RECEIVED FROM TCM
1. OUTLINE OF DIAGNOSIS
Detect malfunction of CAN communication.
Judge as NG when data received from TCM, VDC CM and combination meter is not normal.
2. COMPONENT DESCRIPTION
(Common Specifications)
CAN Protocol 2.0 B (Active)
Frame Format: 11 Bit ID Frame (Standard Frame)
Conforms to ISO11898
Communication Speed: 500 kbps
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
Judge as NG when the following conditions are established.
Time Needed for Diagnosis: 2 seconds
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
HC:DTC U0416 INVALID DATA RECEIVED FROM VEHICLE DYNAMICS CON-
TROL MODULE
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC U0402. <Ref. to GD(w/o STI)-243, DTC U0402 INVALID DATA RE-
CEIVED FROM TCM, Diagnostic Trouble Code (DTC) Detecting Criteria.>
HD:DTC U0423 INVALID DATA RECEIVED FROM INSTRUMENT PANEL CLUS-
TER CONTROL MODULE
1. OUTLINE OF DIAGNOSIS
NOTE:
For the detection standard, refer to DTC U0402. <Ref. to GD(w/o STI)-243, DTC U0402 INVALID DATA RE-
CEIVED FROM TCM, Diagnostic Trouble Code (DTC) Detecting Criteria.>
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
Data updated from control module connected to CAN None
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GD(w/o STI)-244
Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
HE:DTC U1712 LOST LIN COMMUNICATION WITH BATTERY "1" MONITOR
MODULE
1. OUTLINE OF DIAGNOSIS
Detect malfunction of LIN communication.
Judge as NG when LIN communication failure has occurred with the battery sensor.
2. COMPONENT DESCRIPTION
The battery sensor monitors the data of battery voltage, current, temperature, etc. ECM receives these data
via LIN communication with the battery sensor.
3. ENABLE CONDITIONS
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously after the enable conditions have been established.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 2 seconds
Malfunction Indicator Light Illumination: Does not illuminate.
Secondary Parameters Enable Conditions
Battery voltage 10.9 V
Judgment Value
Malfunction Criteria Threshold Value
Data received from control modules connected to LIN Does not change
or
Checksum error
15WRX_STI_US_EN.book 244 ージ 20  
2015 WRX / WRX STI SERVICE MANUAL QUICK REFERENCE INDEX
FUJI HEAVY INDUSTRIES LTD. G1190BE4
TRANSMISSION SECTION
This service manual has been prepared
to provide SUBARU service personnel
with the necessary information and data
for the correct maintenance and repair
of SUBARU vehicles.
This manual includes the procedures
for maintenance, disassembling, reas-
sembling, inspection and adjustment of
components and diagnostics for guid-
ance of experienced mechanics.
Please peruse and utilize this manual
fully to ensure complete repair work for
satisfying our customers by keeping
their vehicle in optimum condition.
When replacement of parts during
repair work is needed, be sure to use
SUBARU genuine parts.
All information, illustration and specifi-
cations contained in this manual are
based on the latest product information
available at the time of publication
approval.
CONTROL SYSTEMS CS
CONTINUOUSLY VARIABLE
TRANSMISSION
CVT(TR690)
CONTINUOUSLY VARIABLE
TRANSMISSION (DIAGNOSTICS)
CVT(diag)
GENERAL DESCRIPTION (CVT) GD(CVT)
MANUAL TRANSMISSION AND
DIFFERENTIAL
6MT(TY75)
MANUAL TRANSMISSION AND
DIFFERENTIAL
6MT(TY85)
MANUAL TRANSMISSION AND
DIFFERENTIAL (DIAGNOSTICS)
6MT(diag)
CLUTCH SYSTEM CL
15WRX_STI_US_EN.book 1 ペー 01  
15WRX_STI_US_EN.book 2 ペー 01  
CONTROL SYSTEMS
CS
Page
1. General Description ...................................................................................2
2. AT Shift Lock Control System ....................................................................7
3. Select Lever .............................................................................................24
4. Select Cable .............................................................................................42
5. AT Shift Lock Solenoid and “P” Range Switch .........................................50
6. Body Integrated Unit ................................................................................53
7. MT Gear Shift Lever .................................................................................54
8. MT Gear Shift Cable ................................................................................85
9. MT Gear Select Cable ..............................................................................94
10. Reverse Check Cable ............................................................................110
11. General Diagnostic Table .......................................................................127
15WRX_STI_US_EN.book 1 ペー 01